Powders, flakes, or pellets containing salts of a sulfo fatty acid alkyl esters in high concentrations, process for production thereof, granulated detergents, and process for production thereof

ABSTRACT

A process for producing powder, flakes, or pellets containing α-sulfo fatty acid alkylester salt in high concentrations, the process including: (1) a step of preparing a paste containing α-sulfo fatty acid alkylester salt by a series of reactions of sulfonating a fatty acid alkylester with a sulfonating gas by contact with each other, esterifying the sulfonated product with a lower alcohol, neutralizing the esterified product, and bleaching the neutralized product, to give a paste containing α-sulfo fatty acid alkylester salt; (2) a step of aging the thus obtained paste; (3) a step of making the aged paste into flakes or pellets containing equal to or less than 10 wt % of water, or a step of making the aged paste into flakes or pellets containing equal to or less than 10 wt % of water and then crushing the resulting flakes or pellets into a powder having an average particle diameter of 100-1500 μm; and (4) a step of aging the powder, flakes, or pellets.

TECHNICAL FIELD

The present invention relates to powder, flakes, or pellets containingin high concentrations α-sulfo fatty acid alkylester salt which, uponconcentration, yields an extremely white powder with reduced odor andimproved storage properties, and a process for production thereof. Thepresent invention relates also to a granular detergent and a soliddetergent containing the powder, flakes, or pellets, and a process forproduction thereof.

BACKGROUND ART

An α-sulfo fatty acid alkylester salt usually takes on an aqueous pasteupon neutralization. In order to handle it in the form of concentrate orpowder, it is necessary to dewater it somehow or the other. There aretwo typical processes. One consists of dissolving in water an Q-sulfofatty acid alkylester salt and an inorganic powder to give a slurrycontaining about 20-70 wt % of water and subsequently spray-drying it togive a dry powder, and the other consists of directly mixing together anα-sulfo fatty acid-alkylester salt (in paste form containing 20-30 wt %of water) and an inorganic powder to give desired particles.

The former process yields a powder containing an α-sulfo fatty acidalkylester salt in comparatively high concentrations because it involvesa drying step. However, it consumes much energy and gives off much wastegas into the atmosphere, which would increase environmental loads.Consequently, it is getting out of date recently. Moreover, productionthrough a slurry with a high water content poses a problem withhydrolysis.

As compared with the former process, the latter process can be run withless energy consumption and less environmental loads. However, itpresents great difficulties in granulation because α-sulfo fatty acidalkylester salt contains a large amount of water and gives a mixtureresembling a paste when its content is high. In addition, the high watercontent also poses a problem with hydrolysis as in the case of spraydrying.

In order to address the above-mentioned problems, there have beenproposed various processes for concentration and powderization. Amongthem is a process involving granulation or powderization of highlyconcentrated anionic surfactant by means of a film evaporator (JapanesePatent Laid-open No. Hei 5-331496). This process, however, tends to givea product which is poor in flowability at 40° C. or above. Moreover,α-sulfo fatty acid alkylester salt is difficult to powderize by crushingat a high temperature immediately after concentration. Another processis designed to produce a granular detergent efficiently withoutappreciable sticking to the crushing machine by concentrating a slurrycontaining an anionic surfactant to give a weight containing equal to orless than 10% of water and crushing it after cooling to 20-70° C.(Japanese Patent Laid-open No. Hei 8-157894). However, this processremains the problem with caking under pressure immediately afterpowderization.

Further another process is designed to produce particles with improvedflowability and solubility by concentrating a slurry containing ananionic surfactant to give particles containing equal to or less than10% of water and having an average particle diameter of 200-1000 μm andthen coating the particles with 1-15 wt % of water-insoluble fine powder(Japanese Patent Laid-open No. Hei 9-87700). This process, however,poses a problem with caking under pressure which occurs immediatelyafter granulation. Further another process is designed to use two kindsof evaporators for concentration of anionic surfactant slurry in orderto save electric power and prevent discoloration due to thermaldegradation (Japanese Patent Laid-open Nos. Hei 10-88197 and Hei11-172299). The problem with this process is that the resulting powderis poor in flowability and liable to caking under pressure.

DISCLOSURE OF INVENTION

An object of the present invention is to provide powder, flakes, orpellets (which exhibit good properties during storage, such asanti-caking under pressure and flowability) containing α-sulfo fattyacid alkylester salt in high concentrations and to provide a process forproduction thereof. Despite the high content of α-sulfo fatty acidalkylester salt, the powder, flakes, or pellets have improved color andreduced odor owing to the specific sulfonating method employed. Anotherobject of the present invention is to provide a granular detergent or asolid detergent containing the powder, flakes, or pellets, and toprovide a process for production thereof.

The present inventors have found that it is possible to obtain powder,flakes, or pellets with improved color and reduced odor if they areformed from an aged paste obtained by sulfonating a fatty acidalkylester used as a raw material, esterifying the sulfonated product,neutralizing the esterified product, and bleaching the neutralizedproduct. The present inventors have also found that the powder, flakes,or pellets containing α-sulfo fatty acid alkylester salt in highconcentrations exhibit good properties (anti-caking under pressure andflowability) during storage if they are aged after they have been formedfrom a concentrated paste (with a water content equal to or less than 10wt %) containing α-sulfo fatty acid alkylester salt.

The present invention provides the following.

[1] A process for producing powder, flakes, or pellets containingα-sulfo fatty acid alkylester salt in high concentrations, said processcomprising:

(1) a step of preparing a paste containing α-sulfo fatty acid alkylestersalt by a series of reactions of sulfonating a fatty acid alkylesterwith a sulfonating gas by contact with each other, esterifying thesulfonated product with a lower alcohol, neutralizing the esterifiedproduct, and bleaching the neutralized product, to give a pastecontaining α-sulfo fatty acid alkylester salt;

(2) a step of aging the thus obtained paste;

(3) a step of making the aged paste into flakes or pellets containingequal to or less than 10 wt % of water, or a step of making the agedpaste into flakes or pellets containing equal to or less than 10 wt % ofwater and then crushing the resulting flakes or pellets into a powderhaving an average particle diameter of 100-1500 μm; and

(4) a step of aging the powder, flakes, or pellets.

[2] The process as defined in [1] which further comprises a step ofmixing the powder, flakes, or pellets with an inorganic powder having anaverage particle diameter of 0.1-100 μm, in an amount of 1-40 wt % ofthe powder, flakes, or pellets.

[3] The process as defined in [1] or [2] wherein the fatty acidalkylester has an iodine value equal to or lower than 1.

[4] Powder, flakes, or pellets containing α-sulfo fatty acid alkylestersalt in high concentrations, which are obtained by the process definedin any one of [1] to [3].

[5] The process for producing a granular detergent which comprisesmixing or granulating the powder, flakes, or pellets obtained by theprocess defined in any one of [1] to [3] together with a detergentcomponent by any method selected from powder mixing, kneading-crushing,and agitation granulation.

[6] The process for producing a granular detergent which comprisesmixing the powder, flakes, or pellets obtained by the process defined inany one of [1] to [3] together with a detergent component and water, togive a slurry containing 20-50 wt % of water, and spray-drying theslurry.

[7] The process for producing a granular detergent which comprisesmixing or granulating the granular detergent obtained by the processdefined in [5] or [6] further with a detergent component by any methodselected from powder mixing, kneading-crushing, and agitationgranulation.

[8] The granular detergent obtained by the process defined in any one of[5] to [7].

[9] The process for producing a solid detergent which comprises mixingand kneading the powder, flakes, or pellets obtained by the processdefined in any one of [1] to [3] together with a detergent component, toobtain solid detergent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart showing an example of the process for producing apaste containing α-sulfofatty acid alkylester salt according to thepresent invention.

FIG. 2 is a schematic diagram showing an example of an apparatus usedfor the process according to the present invention.

FIG. 3 is a schematic diagram showing an example of a sulfonatingreactor.

FIG. 4 is a schematic diagram showing an example of a reactor used fortubular gas-liquid multiphase flow reaction (pseudo-film reaction).

BEST MODE FOR CARRYING OUT THE INVENTION

Some terms used in the present invention are defined as follows.

“Powder” is a powdery or particulate material having an average particlediameter of 100-1500 μm.

“Flakes” is a flaky material measuring 1-200 mm in length and width and0.2-5 mm in thickness.

“Pellets” is a cylindrical material formed by an extruder (such aspelleter), having a diameter of about 5-15 mm and an average length of5-50 mm.

“Containing in high concentrations” means that the powder, flakes, orpellets contain α-sulfo fatty acid alkylester salt in an amount no lessthan 50 wt % (net), preferably no less than 75 wt % (net).

“Average particle diameter” is the value calculated from the formulabelow after classification using a sieve and receiving pan. The sieveshould preferably be one which is prescribed in JISZ 8801-1:2000 for“Testing sieve, Part 1, metal net sieve”. Incidentally, particles havingan average particle diameter equal to or smaller than 100 μm weremeasured by using an apparatus for measuring the particle sizedistribution by laser light scattering (Model LDSA-1400A, from TohnichiComputer Applications).Average particle diameter (weight50%)=10^((50−(c−d/(log b−log a)×log b))/(d/(log b−log a)))where,

-   -   a: the opening (in μm) of the first sieve for which the weight        frequency is 50% or more.    -   b: the opening (in μm) of the sieve having an opening one step        larger than a μm.    -   c: the accumulated weight frequency (in %) of samples collected        from the receiving pan and the sieves having openings up to a        μm.    -   d: the weight frequency (in %) of samples collected from the        sieve having an opening of a μm.        Production Method of Paste Containing α-Sulfo Fatty Acid        Alkylester Salt

According to the present invention, the process for producing powder,flakes, or pellets containing α-sulfo fatty acid alkylester salt in highconcentrations starts with a first step of preparing a paste containingα-sulfo fatty acid alkylester salt.

-   (1) The first step includes a series of reactions of sulfonating a    fatty acid alkylester with a sulfonating gas by contact with each    other, esterifying the sulfonated product with a lower alcohol,    neutralizing the esterified product, and bleaching the neutralized    product, thereby giving a paste containing α-sulfo fatty acid    alkylester salt. The bleaching may be carried out before    neutralizing.

FIG. 1 is a flowchart showing an example of the process for producing apaste containing α-sulfo fatty acid alkylester salt according to thepresent invention. FIG. 2 is a schematic diagram showing an example ofthe apparatus used for production. FIG. 3 is a schematic diagram showingan example of the sulfonating reactor. The apparatus shown in FIG. 2uses the following materials for each reaction under the conditionspecified. Fatty acid methylester as a fatty acid alkylester (rawmaterial). SO₃ gas diluted with dehumidified air or nitrogen gas as asulfonating gas. Na₂SO₄ (sodium sulfate) as a discoloration inhibitor.Methanol as a lower alcohol. NaOH aqueous solution as an alkalineaqueous solution. H₂O₂ (hydrogen peroxide) as a bleaching agent. In FIG.2, “%” means “wt %”. Thus, FIG. 2 should be interpreted to mean thatNa₂SO₄ is used as much as 5 wt % for the raw material, methanol is usedas much as 4 wt % for sulfonic acid, and hydrogen peroxide is used asmuch as 1.0 wt % (on net basis) for the active ingredient (α-sulfo fattyacid alkylester salt).

A description is given below with reference to FIGS. 2 and 3 about theprocess for production of a paste containing α-sulfo fatty acidalkylester salt.

First, a reaction vessel 1 of mixing type for batch process (equippedwith a stirrer) is charged with a fatty acid alkylester (as the rawmaterial) and a discoloration inhibitor.

The fatty acid alkylester as the raw material is not specificallyrestricted; it includes animal fat and oil (such as beef tallow, fishoil, and lanolin), vegetable oil (such as coconut oil, palm oil, andsoybean oil), and synthetic fatty acid alkylester derived from α-olefinby the oxo process. Their typical examples are listed below.

Methyl laurate, ethyl laurate, and propyl laurate. Methyl myristate,ethyl myristate, and propyl myristate. Methyl palmitate, ethylpalmitate, and propyl palmitate. Methyl stearate, ethyl stearate, andpropyl stearate. Hardened tallow fatty acid methyl, ethyl, and propyl.Hardened fish oil fatty acid methyl, ethyl, and propyl. Palm oil fattyacid methyl, ethyl, and propyl. Palm oil fatty acid methyl, ethyl, andpropyl. Palm kernel oil fatty acid methyl, ethyl, and propyl. They maybe used alone or combination with one another.

According to the present invention, the fatty acid alkylester as the rawmaterial should have an iodine value no larger than 1, preferably nolarger than 0.5. The lower is the iodine value, the more desirable isthe material from the standpoint of color and odor. The raw materialwith an iodine value in excess of 1 is good in color.

A desirable fatty acid alkylester in the present invention is one whichis represented by the formula (1) below.R¹CH₂COOR²   (1)(wherein, R¹ is a C₆₋₂₄ straight or branched alkyl group or alkenylgroup, and R² is a C₁₋₆ straight or branched alkyl group.)

It is desirable to carry out sulfonation in the presence of adiscoloration inhibitor in order to obtain a light-colored α-sulfo fattyacid alkylester. The discoloration inhibitor is a monovalent metal saltof organic acid or inorganic sulfuric acid, with the latter beingpreferable. Organic salts are exemplified by sodium formate, potassiumformate, and sodium acetate. Inorganic sulfates are exemplified bysodium sulfate, potassium sulfate, and lithium sulfate, which aremonovalent metal salts in the form of anhydrous powder. Inorganicsulfates are inexpensive and yet highly effective in preventingdiscoloration. They are a common ingredient incorporated into detergentand hence they do not need to be removed from the α-sulfo fatty acidalkylester salt to be used for detergent.

The discoloration inhibitor should preferably have an average particlediameter no larger than 250 μm, especially preferably no larger than 100μm. The reason for this is that the one having a small particle diameterdisperses well into the liquid phase of the raw material owing to itslarge contact area, thereby enhancing its effect. (It should be notedthat an inorganic sulfate hardly dissolves but mostly remains dispersedin the liquid phase of the raw material during reaction.) Thediscoloration inhibitor should preferably be added in an amount of 0-30wt %, more preferably 0.5-20 wt %, further preferably 3-20 wt %, for thefatty acid alkylester as the raw material. It will not produceadditional effect when used in an amount in excess of 30 wt %.

Although a reactor of vessel type (rector vessel 1) is used in figure,it is possible to use a reactor of any other type suitable for filmreaction or tubular gas-liquid multiphase flow reaction. The process forsulfonation is not specifically restricted, but it includes filmsulfonation and batch-type sulfonation. In the case of batch-typesulfonation, a reactor of vessel type is desirable because when thediscoloration inhibitor is used at the time of sulfonation, it shouldpreferably be uniformly dispersed into the raw material for contact withthe sulfonating gas.

The raw material in the reactor vessel 1 is raised to a prescribedreaction temperature, with stirring by the stirrer 3. Thus, there isobtained the raw material liquid phase 2, which is composed of the rawmaterial (in liquid form) and the discoloration inhibitor (inparticulate form) dispersed therein. The reaction temperature is atemperature at which the fatty acid alkylester exhibits flowability.Usually, it is the melting point of the fatty acid alkylester,preferably 70° C. above the melting point.

A sulfonating gas is introduced into the raw material liquid phase 2through the sulfonating gas inlet 4. The sulfonating gas is introducedthrough the gas sparger 5 a connected to the gas inlet 5, and it isdispersed into the raw material liquid phase 2 by the stirrer 3. At thesame time, the discoloration inhibitor (in particulate form) isuniformly dispersed into the raw material liquid phase 2.

The sulfonating gas should be introduced from the gas sparger 5 a at arate preferably no lower than 10 m/sec, more preferably 50-200 m/sec.Introducing with a flow rate lower than 10 m/sec will produce largebubbles.

The stirrer 3 should be run such that the tip speed of the end of theblade 3 b is preferably 0.5-6.0 m/sec, more preferably 2.0-5.0 m/sec.Stirring at a tip speed lower than 0.5 m/sec will result in incompletebubble dispersion and low reaction rates. This weakens the effect ofpreventing discoloration because the discoloration inhibitor is notdispersed completely. On the other hand, vigorous stirring at a tipspeed in excess of 6.0 m/sec will not produce any additional effect butincreases power consumption.

In this step, the sulfonating gas should usually be introduced over aperiod of 10-180 minutes for production efficiency. This period may beextended over 180 minutes if prevention of discoloration is moreimportant than production efficiency. Extending the period for slowcontact between the sulfonating gas and the raw material liquid phase 2prevents the α-sulfo fatty acid alkylester from discoloration.

The sulfonating gas may be SO₃ gas or fuming sulfuric gas, with theformer being preferable. The SO₃ gas should preferably be used afterdilution to 1-40 vol % with dehumidified air or nitrogen (or any otherinert gas). Excessively diluted SO₃ gas (lower than 1 vol %), whichmeans a volume of the sulfonating gas is large, will need a largereactor to hold it. The large reactor may causes inconvenient. On theother hand, insufficiently diluted SO₃ gas (higher than 40 vol %) willbring about vigorous reactions, giving rise to more by-products andcausing discoloration to sulfonated products such as α-sulfo fatty acidalkylester. Especially, in the case where the sulfonated product isα-sulfo fatty acid alkylester, dilution to 1-30 vol % is desirable toprevent its discoloration.

The molar amount of SO₃ gas used for reaction should suitably be 1.0-2.0times, preferably 1.0-1.7 times, more preferably 1.05-1.5 times, theamount of the raw material. The molar amount less than 1.0 times may benot enough for complete sulfonation. The molar amount in excess of 2.0times causes vigorous sulfonation, which results in by-products anddiscoloration.

After introduction of sulfonating gas into the raw material liquid phase2 as mentioned above, the reaction vessel 1 should be kept at aprescribed temperature for aging. This aging temperature shouldpreferably be 70-100° C. Aging below 70° C. does not proceed rapidly,and aging above 100° C. causes discoloration.

Aging should preferably last for 1-120 minutes. During aging, thestirrer should be run so that the stirring blades 3 b keep theprescribed tip speed as mentioned above. This helps the discolorationinhibitor to uniformly disperse during aging. In this example in FIG. 2,sulfonation is carried out at 80° C. for 1 hour and aging is carried outat 80° C. for 30 minutes.

Then, the sulfonating step is followed by esterification with loweralcohol. This step is intended to suppress by-products and to improvethe purity of the α-sulfo fatty acid alkylester salt, and hence it maybe omitted if the above-mentioned sulfonation and aging give highly pureα-sulfo fatty acid alkylester (with little SO₃ di-adduct in the reactionsolution). However, this step should preferably be carried out.

The lower alcohol for esterification should preferably be one which hasthe same carbon number (1 to 6) as the alcohol residue in the fatty acidalkylester as the raw material, although it is not specificallyrestricted. It should be used suitably in a molar amount 0.5-10 times,preferably 0.8-5.0 times, the SO₃ di-adduct in the reaction solution. Amolar amount less than 0.5 times may be not enough for completeesterification. A molar amount more than 10 times may be not produce anyadditional effect but needs recovery of excess lower alcohol. Thereaction temperature should suitably be 50-100° C., preferably 50-90°C., and the reaction time should be 5-120 minutes. In this FIG. 2example, they are 80° C. and 30 minutes.

After esterification, the sulfonated product is discharged from theesterification reaction vessel 10 and then supplied to the neutralizingline 17 by the esterified acid supply pump 12, so that it is neutralizedwith an alkaline aqueous solution. Neutralization should be carried outso as to give a neutralized product in which the concentration of theactive ingredient (purity content of α-sulfo fatty acid alkylester salt)is preferably 10-80 wt %, more preferably 60-80 wt %, further preferably62-75 wt %. It is 70 wt % in the process under the condition shown inFIG. 2. In the range of 10 wt % to 60 wt %, the neutralized productincreases in viscosity in proportion to concentrations, withproductivity being poor at low concentrations. In the range of 60 wt %to 80 wt %, the neutralized product has a low viscosity adequate forgood handling and productivity.

The alkaline aqueous solution should be any aqueous solution of alkalimetal hydroxide, alkaline earth metal hydroxide, ammonia, orethanolamine. The concentration of the alkaline aqueous solution shouldpreferably be no higher than 50 wt %, more preferably 15-50 wt %. If theconcentration is lower than 15 wt %, the resulting neutralized productwill not contain the active ingredient (α-sulfo fatty acid alkylestersalt) in the desired concentration (from 60 wt % to 80 wt %). In thisFIG. 2 example, the concentration of the alkaline solution is 34 wt %.In the present invention, preliminary neutralized product shouldsuitably be mixed with the sulfonated product by premixer 14. Theneutralized product (or preliminary neutralized product) to be added tothe sulfonated product should suitably be 5-25 times, preferably 10-20times, the total amount (in weight) of the sulfonated product and thealkaline aqueous solution added thereto. An amount less than 5 times maybe not enough to suppress by-products. An amount more than 25 times maybe unfavorable to productivity. In this example, the amount is 20 times.

The neutralized product decreases in viscosity due to residual loweralcohol in the neutralizing step as mentioned above. This preventsα-sulfo fatty acid dialkali salt (as by-product) from occurring due topartial contact between the sulfonated product and the locallyconcentrated alkaline aqueous solution that takes place in the initialstage of reaction. In addition, the presence of lower alcohol suppressesthe occurrence of by-products. Incidentally, the temperature ofneutralization should suitably be 30-140° C., preferably 50-120° C.,more preferably 50-100° C., and the duration of neutralization shouldpreferably be 10-60 minutes. Also, the neutralizing step shouldpreferably be carried out such that the mixture of the sulfonatedproduct and the alkaline aqueous solution is acid or weakly alkaline (pH4-9). If the mixture is strongly alkaline, the ester linkage is likelyto break. The neutralizing step in the present invention may also beaccomplished by reacting the sulfonic acid with a solid metal carbonateor hydrogen carbonate instead of using the alkaline aqueous solution.Neutralization with concentrated soda ash (as a solid metal carbonate)is desirable because of its lower price than other bases. In addition,neutralization with the solid metal carbonate yields a reaction mixturecontaining a less amount of water, preventing it from becoming stronglyalkaline. A metal carbonate has an advantage over a metal hydroxide ingenerating a less amount of heat of neutralization. Examples of themetal carbonate or hydrogen carbonate include sodium carbonate,potassium carbonate, ammonium carbonate, sodium hydrogencarbonate,potassium hydrogencarbonate, and ammonium hydrogencarbonate, inanhydrous or hydrate form. They may be used alone or in combination withone another. In this FIG. 2 example, the neutralizing step is carriedout at 70° C. for 20 minutes.

The neutralizing step should preferably be preceded or followed by astep of improving (or bleaching) the color of the α-sulfo fatty acidalkylester salt with a bleaching agent. The bleaching step shouldpreferably be placed after the neutralizing step.

Examples of the bleaching agent include hydrogen peroxide andhypochlorite in the form of aqueous solution in any concentration. Thebleaching agent should suitably be used in an amount of 0.1-10 wt %,preferably 0.1-5 wt % (on net basis), for the amount of the activeingredient(α-sulfo fatty acid alkylester salt). In this FIG. 2 example,the bleaching agent is used in an amount of 1.0 wt % (on net basis) forthe amount of the active ingredient. In this FIG. 2 example, thebleaching step is intended to bleach the neutralized product. Theadvantage of bleaching in this manner over the conventional bleachingprocess, which is carried out at the same time as the sulfonated productis esterified, is that bleaching keeps the neutralized product stablewithout side reactions (due to esterification) and achieves its objectwith a less amount of bleaching agent than is required in theconventional process. In this FIG. 2 example, the amount of hydrogenperoxide is 1.0 wt % (on net basis) for the amount of the activeingredient. The preliminary bleached product (the neutralized productwhich has been mixed with the bleaching agent) should preferably bemixed in an amount of 5-30 times (in weight) the neutralized productwhich may be not yet bleached. An amount less than 5 times does notproduce the effect of suppressing by-products. An amount more than 30times will adversely affect productivity.

The bleaching temperature should suitably be 50-140° C., preferably60-120° C., for hydrogen peroxide, and 30-80° C. for hypochlorite. Thebleaching agent should be supplied such that the total reaction time inthe mixing line 21 and the bleaching line 23 is about 30-360 minutes. Inthis FIG. 2 example, the bleaching temperature is 80° C. and thereaction time is 3 hours. Incidentally, bleaching should preferably becarried out at pH 4-9.

A heating step may be placed between the neutralizing step and thebleaching step, although it is not shown in FIG. 2. This heating stepwill improve the color of the finished powder. To this end, theneutralized product should suitably be heated 80° C. or above,preferably at 80-170° C., suitably for 0.5 hours to 7 days, preferably 1hour to 5 days, more preferably 2-24 hours.

-   (2) The first aging step for aging the resulting paste

The paste containing α-sulfo fatty acid alkylester salt is transferredto the bleaching tank 25, in which it undergoes the first aging step forcolor improvement. Aging is defined as the process of keeping the pasteat a prescribed temperature for a prescribed period of time. The agingtemperature should suitably be 60-90° C., preferably 70-80° C. The agingperiod should suitably be 1-48 hours, preferably 2-24 hours, morepreferably 2-12 hours. Aging at a temperature below 60° C. or aging fora period less than 1 hour will not improve the color of the paste. Agingat a temperature above 90° C. or aging for a period more than 48 hourswill hydrolyze the α-sulfo fatty acid alkylester salt. The foregoingstep gives the paste containing α-sulfo fatty acid alkylester salt whichis used as the raw material for powder, flakes, or pellets.

-   (3) The step of making the aged paste into flakes or pellets    containing equal to or less than 10 wt % of water, or the step of    making the aged paste into flakes or pellets containing equal to or    less than 10 wt % of water and then crushing the resulting flakes or    pellets into powder having an average particle diameter of 100-1500    μm.

The paste containing α-sulfo fatty acid alkylester salt which has beenobtained by the above-mentioned step is subsequently concentrated togive flakes or pellets containing equal to or less than 10 wt % ofwater. The apparatus and method for concentration are not specificallyrestricted. Some examples are: open-type mixer (vertical kneader andribbon mixer), for mixing and concentrating at 70-120° C. for 1-15hours; film evaporator (“Evaolator” from Sakura Seisakusho, “Exeva” fromShinko Pantec, “Kontro” from Hitachi Ltd.) and SVC concentrator (fromSakuma Seisakusho) for flash concentration by vacuum evaporation in anevaporator at a reduced pressure; and drum-type concentrator (CD drierfrom Nishimura Tekkousyo), self-cleaning-type concentrator (SC processorfrom Kurimoto), and custom drier (from Okawara MFG).

In the present invention, it is desirable to use the film evaporator andflash concentrator from the standpoint of productivity.

The film evaporator should be run in the following manner. First, thepaste containing Q-sulfo fatty acid alkylester salt is fed into acylindrical casing equipped with stirring blades or puddles. The pasteis spread over the heat-conducting surface by the centrifugal force ofthe stirring blades. Water and low-boiling components evaporate by heat(from the heating medium circulating through the wall jacket) andstirring heat. The amount of water to be evaporated may be controlled byadjusting the rate at which the paste is added, the revolution and tipspeed of the stirring blades, the clearance between the wall surface andthe blade ends, the degree of vacuum in the concentrator, and the jackettemperature. The tip speed of the stirring blades should preferably be5-30 m/s, more preferably 5-25 m/s. Stirring at a lower speed than 5 m/swill not spread the paste completely over the wall surface and performsmooth liquid exchange. On the other hand, stirring at a higher speedthan 30 m/s will produce frictional heat, thereby raising thetemperature of the concentrated product and increasing mechanical loadon the concentrator.

The clearance between the wall surface and the blade end shouldpreferably be 0.5-5 mm, more preferably 1-4 mm, and most desirably 1-3mm. A clearance smaller than 0.5 mm will prevent stable operation infull-size machine for mass production. A clearance larger than 5 mm willprevent the spreading and liquid exchange of the concentrated paste.

The degree of vacuum in the concentrator should preferably be 0.0040 MPato the atmospheric pressure, more preferably 0.0040 MPa to 0.067 MPa. Ata pressure lower than 0.0040 MPa, it may be difficult to discharge theconcentrated product (with a high viscosity) from the concentrator. Onthe other hand, at a pressure higher than the atmospheric pressure,water vapor may become saturated in the film evaporator, therebydecreasing the efficiency of evaporation.

The size of the concentrator is not specifically restricted. Thecylindrical casing may be 0.2-1.0 mm in inside diameter and 0.5-10 mlong (heat conducting part), with the heat conducting area of 0.2-126m². The residence time on the heat-conducting surface in theconcentrator should preferably be 0.15 seconds to 10 minutes, morepreferably 0.3 seconds to 10 minutes.

The flash concentration is accomplished by injecting the heated pastecontaining α-sulfo fatty acid alkylester salt into a flash evaporator.Thus, there is obtained a concentrated and dried paste containingα-sulfo fatty acid alkylester salt. Flash evaporation brings aboutevaporation immediately as soon as a liquid is fed into a flashevaporator under reduced pressure from an atmosphere at a hightemperature and pressure. The pressure in the flash evaporator shouldpreferably be 0.0010 MPa to atmospheric pressure. The water content inthe concentrated product may be controlled by regulating the pressure inthe flash evaporator, the jacket temperature of the heater, and the flowrate of the paste.

The concentrated paste, which contains equal to or less than 10 wt % ofwater, is usually a viscous paste which is as hot as above 70° C.immediately after the step of concentration. At such a high temperature,it is too sticky to be crushed readily by a crusher.

Therefore, in the present invention, the concentrated paste shouldpreferably be cooled prior to the subsequent steps for crushing. In thiscase, the cooling may preferably be simultaneously with or after flakingor pelletizing. By these steps, the concentrated paste can beless-sticky, so enable to be processed sufficiently. The temperatureafter cooling is preferably 20-70° C., more preferably 20-60° C.

The cooling apparatus and method are not specifically restricted. Someexamples are: Air-cooler or belt-type vacuum cooler (“Belmax” fromOkawara MFG) and steel-belt cooler (from Sandvik). Cooling and flakingcan be conducted at the same time by using a drum cooler, such as “DrumFlaker” from Kusunoki Kikai Seisakusho and “Double Drum Dryer” fromKansorn. As mentioned above, it is possible to obtain the concentratedpaste containing α-sulfo fatty acid alkylester salt in the form offlakes simultaneously with cooling, or it is possible to make theconcentrated paste into pellets and then cool them.

The thus obtained flakes or pellets may be crushed into a powder havinga desired average particle diameter by using a crushing-granulator, ifnecessary. The crushing-granulator is not specifically restricted.Desirable ones are listed below.

A crushing-granulator equipped with a rotor and sieve inside, preferablyan impact crusher, such as hammer mill, atomizer, and pulverizer, and acutting-shearing crusher, such as cutter mill and feather mill. Theirtypical examples include Fitz Mill (from Hosokawamicron), Speed Mill(from Okada Seiko), Power Mill (from Dalton), Atomizer (from FujiPowdal), Pulverizer (from Hosokawamicron), and Comminutor (from FujiPowdal).

The preferred crushes is one which crushes the concentrated pastecontaining α-sulfo fatty acid alkylester salt and then dischargescrushed particles through the screen having a prescribed opening. Ingeneral, it is desirable to introduce cold air into the crusher in orderto prevent the crushed product from softening (due to crushing heat) andsticking to the crusher. The temperature of the cold air shouldpreferably be 5-30° C., more preferably 5-25° C. The cold air shouldpreferably be one which has been dehumidified or diluted with nitrogen.In addition, it is desirable to add grinding aid for crushing, at thetime of grinding. The grinding aid reduces the crushing power, gives thedesired particle size, and improves the powder properties, when added ina small amount into the crusher. Concretely, an inorganic powder, whichmentioned later, is useful.

The screen is not specifically restricted; it may be of wire net type,herringbone type, or punched metal type. The last one is desirable inview of the screen strength and the powder shape.

The crusher may be of hammer type or cutter type mentioned above; thesecond type is desirable from the standpoint of avoiding the occurrenceof fine powder due to impact crushing. The cutter blades should becoated with stellite or tungsten carbide so that they will not wear outafter prolonged operation.

The average particle diameter of the crushed product (powder) should be100-1500 μm, preferably 200-800 μm. Powder with an excessively largeparticle diameter may slow to dissolve during washing, which leads tolow detergency and sticking to clothes. On the other hand, powder withan excessively small particle diameter causes dusting (with finepowder), decreases the crushing yields, and aggravates the flowability.The bulk density of the powder should generally be 0.2-1.4 g/cm³,preferably 0.3-1.0 g/cm³, more preferably 0.4-0.8 g/cm³.

-   (4) The second aging step for aging the powder, flakes, or pellets

The powder, flakes, or pellets containing α-sulfo fatty acid alkylestersalt in high concentrations, which have been produced by the foregoingsteps, subsequently undergo the second aging step.

Aging is defined, in the same way as mentioned above, as the process ofkeeping the product at a prescribed temperature for a prescribed periodof time. The second aging step in the present invention is accomplishedby allowing the powder, flakes, or pellets to stand. Aging in thismanner improves their properties such that they do not cake ordeteriorate in flowability during storage or after they have been madeinto a final product. The aging temperature should preferably be 5-60°C., preferably 10-45° C. Aging at a temperature lower than 5° C. willnot crystallize the α-sulfo fatty acid alkylester salt. Aging at atemperature higher than 60° C. will deteriorate the properties, whichcauses caking. The duration of aging should preferably be equal to orlonger than 10 minutes, more preferably equal to or longer than 30minutes, more preferably longer than 60 minutes. Duration shorter than10 minutes is not enough to crystallize the α-sulfo fatty acidalkylester salt, and this leads to caking during storage in a largestorage tank, such as silo.

The thus obtained powder, flakes, or pellets should be mixed with aninorganic powder for improvement of their properties. The inorganicpowder should have an average particle diameter of 0.1-100 μm,preferably 0.5-50 μm, more preferably 0.5-30 μm. The amount of theinorganic powder should preferably be 1-40 wt %, more preferably 1-30 wt%, further preferably 1-20 wt %. With an average particle diametersmaller than 0.1 μm, the inorganic powder may cause dusting. With anaverage particle diameter larger than 100 μm, the inorganic powder maymake the powder mixture inhomogeneous due to separation during storage.With an amount less than 1 wt %, the inorganic powder can not avoid thatthe powder, flakes or pellets to stick together for coalescence. With anamount more than 40 wt %, the inorganic powder adversely affects theflowability of the powder mixture. The inorganic powder may be mixedwith the flakes or pellets as such or during or after their crushing.The mixing apparatus is not specifically restricted so long as it iscapable of dry mixing. Its typical examples include a horizontalcylindrical mixer, V-type mixer, and agitation granulator.

The inorganic powder may be either a water-soluble one or awater-insoluble one. More than one kind of inorganic powder may besuitably used in combination with one another. The inorganic powder isnot specifically restricted so long as it has the above-mentionedaverage particle diameter. It includes, for example, stearate,aluminosilicate (such as A type zeolite), sodium carbonate, calciumcarbonate, magnesium carbonate, alkaline earth metal carbonate,amorphous silica, white carbon (silica), sodium silicate, calciumsilicate, magnesium silicate and other silicates, clay mineral (such astalc and bentonite), silicon dioxide, titanium dioxide, pulverizedsodium carbonate, sodium sulfate, potassium sulfate, sodiumtripolyphosphate, and sodium citrate.

The flakes or pellets containing the α-sulfo fatty acid alkylester saltwhich have been produced by the process of the present invention may beused in the crushed form after crystallization has proceeded in theα-sulfo fatty acid alkylester salt. In this case, they may be mixed orcoated with one or more than one kind of the above-mentioned inorganicpowder having an average particle diameter of 0.1-100 μm, preferably0.5-50 μm, more preferably 0.5-30 μm, as an agent to prevent them fromsticking to the crusher or to improve the power properties.

If the thus obtained powder causes dusting, a small amount of nonionicsurfactant may be sprayed thereto. By the spraying, it is possible toprevent the scattering of fine powder, thus dusting is reduced.

Process for Production of Granular Detergent

The present invention also provides a process for producing a granulardetergent from the powder, flakes, or pellets produced by theabove-mentioned process, by mixing with or granulating in conjunctionwith detergent components by any one method selected from powder mixing,kneading-crushing, and stirring granulation.

The detergent components are those materials which are incorporated intothe powder, flakes, or pellets produced by the above-mentioned process.They include cleaning agents, bleaching agents, and any other agents toimprove manufacturability and powder properties. They may be selectedwithout specific restrictions from those which are commonly used fordetergents. The detergent components that can be used for the granulardetergent of the present invention include anionic surfactants, nonionicsurfactants, cationic surfactants, amphoteric surfactants, chelatingagents (zeolites and organic builders), neutral inorganic builders,alkaline inorganic builders, anti-redeposition agents, viscositycontrolling agents, softeners, reducing agents, bleaching agent, bleachactivating agents, fluorescent whitening agents, perfumes, enzymes,pigment, surface modifiers, anti-foaming agents, antioxidants, andwater.

The detergent components contained in the detergent are not specificallyrestricted in their form; they may be used as such or in the form ofdetergent particles. The detergent particles are not specificallyrestricted so long as they contain any component which helps theabove-mentioned detergent components to produce their effect. Thosewhich contain both alkaline builder and chelating agent are desirable.No specific restrictions are imposed on the mixing ratio in thedetergent of the detergent components to the powder, flakes, or pelletscontaining the α-sulfo fatty acid alkylester salt in highconcentrations.

The granular detergent is obtained from the powder, flakes, or pelletscontaining the α-sulfo fatty acid alkylester salt in high concentrationsand the detergent components by any one method selected from powdermixing, kneading-crushing, and stirring granulation.

The powder mixing involves mixing the powder containing the α-sulfofatty acid alkylester salt in high concentrations with detergentcomponents, particularly granular detergent components, in an apparatuscapable of powder mixing. Mixing is preferred performed at 5-60° C.,preferably 10-50° C., for 0.5 seconds or more, more preferably 5 secondsor more, most desirably 30 seconds or more. The upper limit of themixing time is not specifically restricted. The apparatus used forpowder mixing is not specifically restricted; horizontal cylindricalmixers, V-type mixers, and agitation granulators are desirable.

The kneading-crushing consists of two stages of kneading and crushing.In the kneading stage, the powder, flakes, or pellets containing theα-sulfo fatty acid alkylester salt in high concentrations are kneadedwith the detergent components by using a continuous kneader (KRC kneaderfrom Kurimoto Tekkosho) or a batch-type kneader (vertical kneader fromDalton) to give a lumpy product. In the crushing stage, the lumpyproduct is crushed by a crusher (Fitz Mill from Hosokawamicron or SpeedMill from Okada Seiko) to give detergent particles. During crushing, thecrusher may be supplied with fine inorganic particles (such as zeolite,sodium carbonate, and white carbon) so that the material being crushedwill not stick to the crusher. It is also desirable to feed cold air asmentioned above.

The stirring granulation forms granules from the powder or flakescontaining the α-sulfo fatty acid alkylester salt in high concentrationsand the detergent components by using a stirring-granulator, such asLoedige mixer (from Matsubo), Shuggy Mixer (from Powlex), High SpeedMixer (from Fukae Kogyo), and Plough-Shear Mixer (from Pacific Machinery& Engineering). If necessary, the resulting granules are classified bycrushing and sieving.

According to an alternative process, the powder, flakes, or pelletsproduced by the above-mentioned process are mixed with the detergentcomponents and water to give a slurry containing 20-50 wt % of water,and the resulting slurry is made into a granular detergent by spraydrying. Upon mixing, the detergent components may be dispersed ordissolved in water. In this case, the mixing ratio (in weight) in thegranular detergent of the powder, flakes, or pellets containing theα-sulfo fatty acid alkylester salt to the detergent components shouldpreferably be from 70:30 to 2:98, more preferably from 30:70 to 5:95,further preferably from 20:80 to 5:95.

The detergent components used in this case may be the same ones asmentioned above. The order in which they are added is not specificallyrestricted. If they contain LAS—H, α-sulfo fatty acid alkylester salt,and alkali builder or zeolite, it is desirable to add LAS—H to theslurry (which has been neutralized), and then add alkali builder orzeolite, and finally add the α-sulfo fatty acid alkylester salt. Thewater content in the slurry should preferably be 20-50 wt %, morepreferably 35-45 wt %. The thus obtained detergent slurry should be keptsuitably at 50-90° C., preferably at 55-80° C.

This slurry is sprayed into a drying tower by using an atomizer of anytype (including pressure nozzle type, air atomizing nozzle type, androtary disk type). An atomizer of pressure nozzle type is desirablebecause the dried powder should suitably have an average particlediameter of 100-700 μm, preferably 150-500 μm. The drying tower issupplied with a hot gas at desirable 150-350° C., preferably 200-280°C., so that the atomized slurry is dried to give spray-dried particles.If the resulting spray-dried powder has an excessively high temperature,it will be poor in flowability with sticking. In order to avoid suchtroubles, the spray-dried product may be supplied with cold air orinorganic fine particles.

The present invention further provides a process for producing agranular detergent by mixing or granulating the granular detergentproduced by the process mentioned above with detergent components by anyone method selected from powder mixing, kneading-crushing, and agitationgranulation. The detergent components used in this process are the sameones as used for mixing or granulation with the powder produced by theabove-mentioned process. Individual components may be the same ordifferent.

The powder mixing, kneading-crushing, and agitation granulation are thesame as mentioned above. The mixing ratio of the spray-dried particlesto the detergent components should preferably be such that the α-sulfofatty acid alkylester salt (on net basis) accounts for 4-90 wt %,preferably 5-54 wt %, more preferably 9-27 wt %.

Process for Production of Solid Detergent

According to the present invention, the powder, flakes, or pelletsproduced by the above-mentioned process may be mixed and kneaded withdetergent components to give a solid detergent. If necessary, water maybe added. The detergent components may be used in the form of granules.Such granules may be formed by any one method selected fromspray-drying, kneading-crushing, or stirring granulation, or any othermethods. Such granules may also be obtained from an acid precursor ofanionic surfactant by neutralization with an alkaline powder.

A description is given below of the process for production of soliddetergent. In the first stage, the powder, flakes, or pellets mentionedabove are mixed with the detergent components (or granules formed fromthem) by using one mixer or two or more mixers arranged in series. Themixer is not specifically restricted. It may be any one of the apparatusused for powder mixing, kneading-crushing, and agitation granulationmentioned above. If necessary, the resulting kneaded mixture may beformed into pellets or strand by using an extrusion-granulator such aspelleter. The resulting mixture is stamped (by using a plodder) to givethe solid detergent. The mixing ratio (by weight) in the solid detergentof the powder, flakes, or pellets containing the α-sulfo fatty acidalkylester salt to the detergent components should preferably be from40:60 to 1:99, more preferably from 30:70 to 3:97, particularly from20:80 to 3:97. Incidentally, the manufacturing process mentioned aboveis merely exemplary and it does not restrict the scope of the presentinvention.

The present invention provides a process for producing powder, flakes,or pellets containing an α-sulfo fatty acid alkylester salt in highconcentrations, and a process for producing a granular detergent orsolid detergent from said powder, flakes, or pellets. The α-sulfo fattyacid alkylester salt according to the present invention exhibits goodpowder properties (flowability and anti-caking under pressure) duringstorage and has improved color and reduced odor.

EXAMPLE

The invention will be described in more detail with reference toExamples and Comparative Examples, which are not intended to restrictthe scope thereof. In the following example, “%” means wt % unlessotherwise indicated.

The powder, flakes, pellets prepared and detergent in each example weremeasured for their properties by the following methods.

<Methods for Evaluation>

(1) Method for Testing the Tendency Toward Caking Under Pressure

A sample is placed in a cylindrical cell, measuring 50 mm in insidediameter and 50 mm in height. The sample is pressed under a load of 3 kgfor 3 minutes at an ambient temperature of 45° C. The molded sample isremoved from the cell and pressed under a load. The load required tobreak the molded sample is measured. The result is rated according tothe following criterion.

<Criterion>

◯: 0 to less than 3 kg

Δ: 3 to less than 4 kg

X: 4 kg or above

(2) Method for Measuring Flowability of Powder (in Terms of Repose Angleθ)

A sample is dropped through a funnel about 20 cm above a board at anambient temperature of 45° C. so that the sample piles up to form a coneon the board. The repose angle θ is calculated from the height and theradius of the base circle.θ: tan θ=height/radiusThe result is rated according to the following criterion.<Criterion>

α: θ≦60°

Δ: 60°<θ≦70°

X: 70°<θ

(3) Method for Measuring the Color of Powder

A sample having a particle diameter of 500-710 μm is measured todetermine the b value by using the Σ90 Color Measuring System (fromNippon Denshoku Industries). The larger is the b value, the moreyellowish is the sample. It is possible to visually distinguish betweentwo samples if their b value difference is greater than 1.0. The resultis rated according to the following criterion.

<Criterion>

◯: b value<13

Δ: 13≦b value<16

X: 16≦b value

(4) Method for Measuring Odor

A sample is placed in a 30 mL glass container, 30 mm in diameter, sothat the glass container is 80 vol % filled. The sample is stored at 50°C. for 2 weeks in the closed glass container. The glass container isopened and the presence or absence of unpleasant odor was determined bysensory test. The results are rated according to the followingcriterion.

<Criterion>

◯: good

Δ: slightly bad

X: very bad

Examples 1 to 4

(1) Preparation of Paste Containing α-Sulfo Fatty Acid Alkylester Salt

(Sulfonating Step)

Sulfonation was carried out by using the reactor shown in FIG. 3. Thisreactor is made of SUS 316L and has a capacity of 200 L. It is equippedwith the cooling jacket and the stirrer 3, so that the reactiontemperature is controlled by the circulating line 7. First, the reactionvessel 1 was charged with 92 kg of fatty acid methyl ester as the rawmaterial. Sodium sulfate (in the form of fine powder) as a discolorationinhibitor was added with thorough stirring, in an amount of 5% for thefatty acid methyl ester. With stirring continued, 110-120 m³ of SO₃ gas(as a sulfonating gas) diluted to 8 vol % with nitrogen gas wasintroduced at a constant flow rate through the ring sparger over 1 hour.The amount of SO₃ gas is equivalent to 1.2 times the amount (in mole) ofthe methyl ester as the raw material. During sulfonation, the reactiontemperature was kept at 80° C. and the cooling medium was circulated ata flow rate of 80-100 L/min through the circulating line 7. Aftersulfonation, the reaction product was kept at 80° C. for 30 minutes.

(Esterifying Step)

Esterification was carried out by using the esterifying reaction vessel10, which is of jacketed three-stage stirring type. For esterification,the reaction vessel was charged with methanol (as lower alcohol) at arate of 3.5-5.5 kg/hr, which is equivalent to 3-4 wt % of the sulfonatedproduct. The temperature of esterification was 80° C., and the agingperiod was 30 minutes.

(Neutralizing Step)

The sulfonated product was discharged from the esterification reactionvessel 10 and continuously supplied to the neutralizing line 17 at aflow rate of 130-135 kg/hr. Neutralization was accomplished by themethod disclosed in Japanese Patent Laid-open No. 2001-64248. Accordingto this method, an aqueous solution (25-35 wt %) of sodium hydroxide wasfed at a constant rate of 50-60 kg/hr to the intermediate point betweenthe premixer 14 and the neutralizing mixer 15. In other words, thesulfonated product was previously and thoroughly mixed with thepreliminary neutralized product by the premixer 14, and the resultingmixture was mixed with the aqueous solution of sodium hydroxide forneutralization. The amount of the preliminary neutralized productcirculating through the loop was 20 times the total amount of thesulfonated product and the alkaline aqueous solution added. Thetemperature of neutralization was kept at 70° C. by adjusting the watertemperature of the heat exchanger 16 of the loop circuit. The residencetime of the neutralized product was 20 minutes. Incidentally, thecirculating loop is equipped with a pH control system (not shown in FIG.2), which controls the supply of the aqueous solution of sodiumhydroxide through a feedback controller. The pressure in the circulatingloop was 4 kg/cm². The resulting neutralized product had pH 6.5.

(Bleaching Step)

The neutralized product was supplied to the bleaching agent mixing line21 at a flow rate of 180-200 kg/hr. The bleaching agent mixing line 21is adapted to circulating loop type, including the circulating line 22equipped with the heat exchanger 20. The circulating line 22 is suppliedwith 35% hydrogen peroxide at a flow rate of 3.5-7.5 kg/hr (1-2% on netbasis for the active ingredient (α-sulfo fatty acid alkylester salt)),so that it is thoroughly mixed therein with the neutralized product(preliminary bleached product) which has been mixed with the bleachingagent. The amount of loop circulation was 15 times the amount of theneutralized product newly added to the preliminary bleached product. Thepressure in the circulating loop pipe was 4 kg/cm². The temperature ofthe circulating loop was adjusted to 80° C. by the heat exchanger 20,and the residence time in the circulating loop was 10 minutes. Thebleached product was introduced into the bleaching line 23 of passagetype, so that bleaching proceeded further. Incidentally, the bleachingline 23 is a jacketed double tube capable of temperature and pressurecontrol. The flow of the bleaching agent mixture was a piston flow, andthe pressure and temperature were adjusted to 4 kg/cm² and 80° C.,respectively. The residence time was 180 minutes.

(2) The First Aging Step

The thus obtained paste containing α-sulfo fatty acid alkylester saltwas transferred to the bleaching tank 25, in which it was aged under thecondition shown in Table 1. The paste which had undergone the firstaging step contained active ingredients (α-sulfo fatty acid alkylestersalt) as shown in Table 1.

(3) Preparation of Powder or Flakes Containing α-Sulfo Fatty AcidAlkylester Salt

(Concentrating Step)

The paste containing α-sulfo fatty acid alkylester salt which had beenobtained by the above-mentioned step was fed into a vacuum filmevaporator (“Exceva” from Shinko Pantec) at a flow rate of 5-90 kg/hr.This evaporator is equipped with stirring blades rotating at 1060 rpm,with the blade tip speed being about 11 m/sec. It has a heat-conductingarea of 0.5 m², an inside diameter of 205 mm, and a clearance of 2-4 mmbetween the heat-conducting surface and the blade end. The paste wasconcentrated at 120-160° C. (the heating temperature of the inside wall)and at a degree of vacuum of 0.007-0.014 MPa. The temperature of theresulting concentrate was 70-100° C. The water content in theconcentrate is shown in Table 1. The concentrate was cooled to 20-30° C.by using a drum flaker (from Kusunoki Kikai Seisakusho). Thus there wereobtained flakes containing α-sulfo fatty acid alkylester salt in highconcentrations.

(Crushing)

The flakes containing α-sulfo fatty acid alkylester salt in highconcentrations, which were obtained in the concentrating step mentionedabove, were fed into the Fitz Mill together with the inorganic powder(according to the formulation shown in Table 1), and dehumidified coldair (at 15° C., with a dew point of −5° C.). In Example 4, ordinarynon-dehumidified cold air at 15° C. was used in place of dehumidifiedcold air. The flow rate of cold air was 6 Nm³/min. Crushing was carriedout at a throughput of 200 kg/hr. Two sets of Fitz mill arranged inseries were used. Fitz Mill is Model DKA-3 of Hosokawamicron. It has afist-stage sieve with an opening of 8 mmφ and a second-stage sieve withan opening of 3.5 mmφ, and a first-stage blade rotating at 4700 rpm anda second-stage blade rotating at 2820 rpm.

(4) The Second Aging Step

The crushed product (or powder) thus obtained underwent aging under thecondition shown in Table 1. Thus there was obtained a powder containingα-sulfo fatty acid alkylester salt in high concentrations. Theproperties of the powder are shown in Table 1.

A description will be given later of the raw materials used.

Examples 5 and 6

Flakes containing α-sulfo fatty acid alkylester salt in highconcentrations were prepared by the same steps (1)-(3) as in Example 1.Without mixing with the inorganic powder, the flakes were fed into twosets of Fitz mill arranged in series together with cold air diluted withnitrogen such that the oxygen content was 8%. Fitz Mill is Model DKA-3of Hosokawamicron. It has a fist-stage screen with an opening of 8 mmφand a second-stage screen with an opening of 3.5 mmφ, and a first-stageblade rotating at 4700 rpm and a second-stage blade rotating at 2820rpm. The flow rate was 6 Nm³/min. Crushing was carried out at athroughput of 150 kg/hr. The resulting crushed product (powder)underwent the second aging step under the condition shown in Table 1.Thus there was obtained a powder containing α-sulfo fatty acidalkylester salt. The properties of the powder are shown in Table 1.

In the following, “according to the method of the specific example”means that it should be a method according to the method described inthe specific example and the materials, the amount and duration shouldconform to those mentioned in the table indicated.

Examples 7 to 9

Sulfonation was carried out by using a gas-liquid mixed phase flowreactor (pseudo-film reactor) shown in FIG. 4 in place of thevessel-type reactor (the reaction vessel 1). The entry part 36 is ajacketed reaction mixer with a capacity of 100 mL. The jacketed reactiontube 41 is a stainless steel tube (SUS 316L), 13.8 mm in inside diameterand 2 m long. Four units of this tube are arranged in parallel. They areconnected to one another through connecting tubes 43, 13.8 mm in insidediameter and 1 m long. The stirring vessel 31 was charged with fattyacid methyl ester (as the raw material) and sodium sulfate (as thediscoloration inhibitor), 5 wt % for the raw material. The stirringvessel was heated to 50° C. and the sodium sulfate was uniformlydispersed into the liquid phase. The mixture was returned to thestirring vessel 31 through the circulating tube 34 by the pump 32 so asto prepare the thoroughly mixed solid-liquid phase. The flow rate in thedischarging tube 33, the circulating tube 34, and the supply tube 35 was0.7 m/sec, and the pressure in these tubes was 2 kg/cm².

The solid-liquid mixed phase was supplied to the entry part 36 from theraw material introducing tube 39 at a constant flow rate of 128 g/min.On the other hand, sulfonating gas (diluted to 8 vol % with nitrogen)was introduced quantitatively through the sulfonating gas introducingtube 38 at a flow rate of 0.3 m³/min in the same way as in Example 1.The temperature of the entry part 36 was 80° C. and the temperature ofthe solid-liquid mixed phase in the reaction tube 41 was adjusted to 80°C. by controlling the cooling water in the jacket. The gas flow rate inthe reaction tube 41 was 30 m/sec, the average thickness of the circularliquid film of the raw material was 0.3 mm, the flow rate was 5 cm/sec,and the residence time was 60 seconds. The sulfonated product wasseparated from the waste gas in the recovery part 45. The sulfonatedproduct was introduced into the vessel-type reactor 1 shown in FIG. 2,and it was aged at a reaction temperature of 80° C. for 30 minutes. Theesterifying step was followed by the same steps as in Example 1. Thusthere was obtained a powder containing α-sulfo fatty acid alkylestersalt. The properties of the powder are shown in Tables 1 and 2.

Examples 10 and 11

Flakes were prepared by the same steps (1)-(3) as in Example 1. In thecase of Example 11, they were mixed with the inorganic powder accordingto the formulation shown in Table 2. Mixing was accomplished by using ahorizontal cylindrical rotary drum (400 mm in diameter, 700 mm long, andhaving an Fr number of 0.14). The flakes (10 kg) and the inorganicpowder in a prescribed amount shown in Table 2 were mixed for 2 minutes(In case of Example 10, they were not mixed with the inorganic powder.).Each resulting flake was aged under the condition shown in Table 2. Thusthere were obtained the desired flakes containing α-sulfo fatty acidalkylester salt in high concentrations. The properties of the flakes areshown in Table 2.

Example 12

The flakes containing α-sulfo fatty acid alkylester salt which had beenobtained in Example 10 were fed into the Fitz mill together withdehumidified cold air at 15° C. (with a dew point of −5° C.) and theinorganic powder as a grinding aid shown in Table 2. The flow rate was 6Nm³/min. Crushing was carried out at a throughput of 100 kg/hr. Thusthere was obtained a powder containing α-sulfo fatty acid alkylestersalt in high concentrations. Two sets of Fitz mill arranged in serieswere used. Fitz Mill is Model DKA-3 of Hosokawamicron. It has afist-stage screen with an opening of 8 mmφ and a second-stage screenwith an opening of 3.5 mmφ, and a first-stage blade rotating at 4700 rpmand a second-stage blade rotating at 2820 rpm. The properties of thepowder are shown in Table 2.

Examples 13 and 14

The paste containing α-sulfo fatty acid alkylester salt which had beenobtained by the steps (1) and (2) in Example 1 was fed into the verticalstirring mixer (from Dalton). The paste had its water evaporated bystirring at a jacket temperature of 90° C. for 8 hours. The resultingconcentrate was made into pellets, measuring about 10 mm in diameter and10-30 mm long on average, by using “Pelleter Double” (Model EXDFJS-60,from Fuji Paudal). In Example 14, the pellets were mixed with theinorganic powder in an amount specified in Table 2. Mixing wasaccomplished by using a horizontal cylindrical rotary drum (400 mm indiameter, 700 mm long, and having an Fr number of 0.14). The inorganicpowder and 10 kg of pellets were fed into the drum; they were mixedtogether for 2 minutes; and then discharged. Thus, the mixture wasobtained (In the case of Example 13, they were not mixed with theinorganic powde.). Subsequently, Each pellet was aged under thecondition shown in Table 2. Thus there were obtained pellets containingα-sulfo fatty acid alkylester salt in high concentrations. Theproperties of the pellets are shown in Table 2.

Example 15

The pellets which had been obtained by the process mentioned in Example13 were fed into the Fitz mill together with cold air (diluted withnitrogen such that the oxygen content was 8%) at 15° C. and theinorganic powder (as a grinding aid) in an amount shown in Table 2. Theflow rate was 6 Nm³/min, and the gas/solid ratio was 2.0 m³/kg. Crushingwas carried out at a throughput of 190 kg/hr to obtain the powdercontaining α-sulfo fatty acid alkylester salt in high concentrations.Two sets of Fitz Mill arranged in series were used. Fitz Mill is ModelDKA-3 of Hosokawamicron. It has a fist-stage screen with an opening of 8mmφ and a second-stage screen with an opening of 3.5 mmφ, and afirst-stage blade rotating at 4700 rpm and a second-stage blade rotatingat 2820 rpm. The properties of the resulting powder are shown in Table2.

Examples 16 to 21

The procedure mentioned in Example 1 was repeated except that theinorganic powder shown in Tables 2 and 3 was used. Thus, there wasobtained the desired powder containing α-sulfo fatty acid alkylestersalt in high concentrations. The mixing of the inorganic powder wascarried out by the procedure mentioned in Example 11. The properties ofthe resulting powder are shown in Tables 2 and 3.

Examples 22 to 24

The paste containing α-sulfo fatty acid alkylester salt which had beenobtained by the steps (1) and (2) mentioned in Example 1 was fed into afilm evaporator at a flow rate of 5-40 kg/hr. This evaporator is“Exceva” (from Shinko Pantec), which is equipped with stirring bladesrotating at 1060 rpm, with the blade tip speed being about 11 m/sec. Ithas a heat-conducting area of 0.5 m², an inside diameter of 205 mm, anda clearance of 2-4 mm between the heat-conducting surface and the bladeend. The paste was concentrated at 120-160° C. (the heating temperatureof the inside wall) and atmospheric pressure. The temperature of theresulting concentrate was at 95° C. The water content in the concentrateis shown in Table 3. The concentrate was cooled to 20-30° C. by using adrum flaker (from Kusunoki Kikai Seisakusho). Thus there were obtainedflakes containing α-sulfo fatty acid alkylester salt in highconcentrations. In Examples 23 and 24, the flakes were crushed intopowder by the procedure mentioned in Example 1. The resulting powder wasaged under the condition shown in Table 3.

Comparative Example 1

The procedure mentioned in Example 1 was repeated to give a powdercontaining α-sulfo fatty acid alkylester salt in high concentrations,whose properties are shown in Table 4.

Comparative Example 2

The procedure mentioned in Example 1 was repeated to give a powdercontaining α-sulfo fatty acid alkylester salt in high concentrations,except that the resulting powder did not undergo aging. The propertiesof the resulting powder are shown in Table 4.

Comparative Example 3

The procedure mentioned in Example 1 was repeated to give flakescontaining α-sulfo fatty acid alkylester salt in high concentrations,except that crushing was not performed and the resulting flakes did notundergo aging. The properties of the resulting flakes are shown in Table4.

Comparative Example 4

The procedure mentioned in Example 14 was repeated to give pelletscontaining α-sulfo fatty acid alkylester salt in high concentrations,except that the resulting pellets did not undergo aging. The propertiesof the resulting pellets are shown in Table 4.

Comparative Example 5

The procedure mentioned in Example 1 was repeated to give a powdercontaining α-sulfo fatty acid alkylester salt in high concentrations,except that the paste containing α-sulfo fatty acid alkylester salt wasconcentrated without aging after it had been transferred to thebleaching tank. The properties of the resulting powder are shown inTable 4.

Incidentally, “Final product” in Tables means the powder, flakes, orpellets which have passed all the steps in Examples 1 to 31. Amount ofinorganic powder and additive in Table 1-5 is amount of raw materialdescribed later. TABLE 1 Example 1 2 3 4 5 6 7 8 Fatty acid methylester*¹ A A B C B A A B Duration of 8 24 3 24 10 8 12 1 aging of paste(hr) Temperature of 80 80 70 90 80 80 60 80 aging of paste (° C.)Concentration of 64.5 68.0 71.4 69.6 66.0 62.5 73.4 66.0 AI in paste (%)Water content 1.8 9.6 4.5 0.9 3.5 1.2 1.6 3.2 in concentrates (%)Inorganic powder used ZeO*² ZeO ZeO ZeO — — ZeO ZeO Average particlediameter 1 1 1 1 — — 1 1 of inorganic powder (μm) Amount of inorganicpowder 10 40 30 5 — — 10 20 (% based on final product) Duration of — — —— — — — — aging of flakes (min) Duration of — — — — — — — — aging ofpellets (min) Duration of 30 60 60 15 60 60 60 60 aging of Powder (min)Aging temperature (° C.) 25 15 15 40 25 25 30 15 Form of final productPowder Powder Powder Powder Powder Powder Powder Powder Average particle480 380 420 250 600 520 1000 730 diameter (μm) Bulk density (g/cm³) 0.610.43 0.49 0.65 0.62 0.60 0.63 0.58 Tendency to caking ◯ Δ ◯ ◯ ◯ ◯ ◯ ◯under pressure Angle of repose ◯ Δ Δ ◯ ◯ ◯ ◯ Δ Color of ◯ ◯ ◯ Δ ◯ ◯ ◯ ◯particulate product Odor ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯*¹Fatty acid methyl ester: refer to table 25*²Zeo: Zeolite

TABLE 2 Example 9 10 11 12 13 14 15 16 Fatty acid methyl ester C A A A AA A A Duration of 18 12 12 12 12 12 12 12 aging of paste (hr)Temperature of 80 80 80 80 80 80 80 80 aging of paste (° C.)Concentration of 64.5 64.5 64.5 64.5 64.5 64.5 64.5 64.5 AI in paste (%)Water content 5.0 1.8 1.8 1.8 2.1 2.1 2.1 1.8 in concentrates (%)Inorganic powder used ZeO — ZeO ZeO — ZeO ZeO Tripoly*³ Average particlediameter 1 — 1 1 — 1 1 50 of inorganic powder (μm) Amount of inorganicpowder 10 — 1 10 — 1 10 15 (% based on final product) Duration of — 6060 60 — — — — aging of flakes (min) Duration of — — — — 60 60 60 — agingof pellets (min) Duration of 60 — — — — — — 60 aging of Powder (min)Aging temperature (° C.) 25 25 25 25 25 25 25 25 Form of final productPowder Flakes Flakes Powder Pellets Pellets Powder Powder Averageparticle 460 — — 480 — — 440 480 diameter (μm) Bulk density (g/cm³) 0.54— — 0.57 — — 0.55 0.62 Tendency to caking ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ under pressureAngle of repose ◯ — — ◯ — — ◯ ◯ Color of Δ — — ◯ — — ◯ ◯ particulateproduct Odor ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯*³Tripoly: Sodium tripolyphosphate

TABLE 3 Example 17 18 19 20 21 22 23 24 Fatty acid methyl ester A A A AA A A A Duration of 12 12 12 12 12 12 12 12 aging of paste (hr)Temperature of 80 80 80 80 80 80 80 80 aging of paste (° C.)Concentration of 64.5 64.5 64.5 64.5 64.5 64.5 64.5 64.5 AI in paste (%)Water content 1.8 1.8 1.8 1.8 1.8 2.3 2.3 2.3 in concentrates (%)Inorganic powder used Citric*⁴ Tripoly/ Potassium*⁵ Sodium*⁶ Citric — —ZeO acid ZeO sulfate/ carbonate/ acid/ ZeO ZeO ZeO Average particlediameter 1 50/1  20/1  20/1  30/1  — — 1 of inorganic powder (μm) Amountof inorganic powder 25 15/10 15/10 15/10 15/10 — — 10 (% based on finalproduct) Duration of — — — — — 60 — — aging of flakes (min) Duration of— — — — — — — — aging of pellets (min) Duration of 60 60 60 60 60 — 6060 aging of Powder (min) Aging temperature (° C.) 25 25 25 25 25 25 2525 Form of final product Powder Powder Powder Powder Powder FlakesPowder Powder Average particle 520 480 430 460 480 — 580 540 diameter(μm) Bulk density (g/cm³) 0.60 0.53 0.54 0.53 0.55 — 0.61 0.58 Tendencyto caking ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ under pressure Angle of repose ◯ ◯ Δ Δ ◯ — ◯ ◯Color of ◯ ◯ ◯ ◯ ◯ — ◯ ◯ particulate product Odor ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯*⁴Citric acid: Pulverized sodium citrate*⁵Potassium sulfate: Pulverized potassium sulfate*⁶Sodium carbonate: Pulverized sodium carbonate [1]

TABLE 4 Comparative Example 1 2 3 4 5 Fatty acid methyl ester A A A A ADuration of 8 8 8 8 — aging of paste (hr) Temperature of 80 80 80 80 —aging of paste (° C.) Concentration of 70.1 70.1 70.1 70.1 70.1 AI inpaste (%) Water content 15.3 8.0 8.0 8.0 4.5 in concentrates (%)Inorganic powder used ZeO ZeO ZeO ZeO ZeO Average particle diameter 1 11 1 1 of inorganic powder (μm) Amount of inorganic powder 30 20 1 1 20(% based on final product) Duration of — — — — — aging of flakes (min)Duration of — — — — — aging of pellets (min) Duration of 60 — — — 60aging of Powder (min) Aging temperature (° C.) 45 — — — 30 Form of finalproduct Powder Powder Flakes Pellets Powder Average particle 490 580 — —520 diameter (μm) Bulk density (g/cm³) 0.61 0.66 — — 0.60 Tendency tocaking X X X X ◯ under pressure Angle of repose Δ ◯ — — ◯ Color of ◯ ◯ —— X particulate product Odor ◯ ◯ ◯ ◯ X

Examples 25 and 26

A mixture was obtained by uniform mixing in a stirring vessel from thepaste containing α-sulfo fatty acid alkylester salt (which had beenobtained by the steps (1) and (2) mentioned in Example 1) and additivesaccording to the formulation shown in Table 5. The resulting mixture wasprocessed by the steps (3) and (4) mentioned in Example 1 to give apowder containing α-sulfo fatty acid alkylester salt in highconcentrations. The properties of the resulting powder are shown inTable 5.

Examples 27 and 28

A mixture was obtained by uniform mixing in a stirring vessel from thepaste containing α-sulfo fatty acid alkylester salt (which had beenobtained by the steps (1) and (2) mentioned in Example 1) and additivesaccording to the formulation shown in Table 5. The resulting mixture wasconcentrated by the step mentioned in Example 13 and then processed(after crushing) by the procedure mentioned in Example 1 to give apowder containing α-sulfo fatty acid alkylester salt in highconcentrations. The properties of the resulting powder are shown inTable 5.

Examples 29 to 31

A concentrate containing α-sulfo fatty acid alkylester salt was obtainedby the steps (1) to (3) mentioned in Example 1. The resultingconcentrate was at 70-100° C., and its water content is shown in Table5. The resulting concentrate was introduced into KRC kneader (Model S-4,from Kurimoto Tekkosho) according to the formulation shown in Table 5.There was obtained a kneaded mixture at 60-90° C. The throughput of thekneader was 50 kg/hr. The kneaded mixture was fed into a pelleter(EXDFJS-60, from Fuji Powdal, with a die opening diameter of 10 mmφ.Thus there were obtained solid pellets, 10 mmφ in diameter and 10-30 mmin average length.

The resulting pellets and the inorganic powder (according to theformulation shown in Table 5) were fed into the Fitz Mill together withdehumidified cold air at 15° C. (with a dew point of −5° C.). The flowrate was 5 Nm³/min. Crushing was carried out at a throughput of 50kg/hr. Two sets of Fitz Mill arranged in series were used. Fitz Mill isModel DKA-3 of Hosokawamicron. It has a fist-stage screen with anopening of 8 mmφ and a second-stage screen with an opening of 3.5 mmφ,and a first-stage blade rotating at 4700 rpm and a second-stage bladerotating at 2820 rpm. The resulting crushed product (powder) underwentaging under the condition shown in Table 5. Thus, there was obtained apowder containing α-sulfo fatty acid alkylester salt in highconcentrations. The properties of the powder are shown in Table 5. TABLE5 Example 25 26 27 28 29 30 31 Fatty acid methyl ester A A A A A A ADuration of 12 12 12 12 12 12 12 aging of paste (hr) Temperature of 8080 80 80 80 80 80 aging of paste (° C.) Concentration of 64.5 64.5 64.564.5 64.5 64.5 64.5 AI in paste (%) Additive polymer*⁷ polymer*⁸ polymerTripoly polymer Tripoly CaO*⁹ 1 2 1 2 Amount of additive 10 5 5 25 10 155 (% based on final product) Water content 3.5 1.8 2.3 1.6 2.0 2.0 2.0in concentrates (%) Inorganic powder used ZeO ZeO ZeO ZeO ZeO ZeO ZeOAverage particle diameter 1 1 1 1 — 1 1 of inorganic powder (μm) Amountof inorganic powder 5 10 10 5 — 10 10 (% based on final product)Duration of 60 60 60 60 60 60 60 aging of Powder (min) Aging temperature(° C.) 25 25 25 25 25 25 25 Average 480 460 470 490 570 530 480 particlediameter (μm) Bulk density (g/cm³) 0.55 0.57 0.54 0.58 0.53 0.55 0.58Tendency to caking ◯ ◯ ◯ ◯ ◯ ◯ ◯ under pressure Angle of repose ◯ ◯ ◯ ◯◯ ◯ ◯ Color of ◯ ◯ ◯ ◯ ◯ ◯ ◯ particulate product Odor ◯ ◯ ◯ ◯ ◯ ◯ ◯*⁷Polymer 1: Acrylic acid/maleic acid copolymer sodium*⁸Polymer 2: Sodium polyacrylate*⁹CaO: Calcium oxide

Examples 32 to 48

(Mixing with Other Particles)

The powder containing α-sulfo fatty acid alkylester salt which had beenobtained in the foregoing examples was mixed with any one kind ofparticles 1 to 5 shown in Tables 6 to 11 according to the formulationshown in Tables 12 and 13. Mixing was accomplished by using a horizontalcylindrical rotary drum (400 mm in diameter, 700 mm long, and having anFr number of 0.14). During mixing for 3 minutes, the mixture was sprayedwith perfume. Thus there was obtained a granular detergent. Theproperties of the granular detergent are shown in Tables 12 and 13. Theparticles 1 to 5 which were added are explained later.

Composition and Preparation of Particles to be Mixed

<Particles 1>

A water-soluble alkaline inorganic salt as one of the components shownin Table 6 below was fed into a Loedige mixer (Model M-20, from Matsubo)equipped with plough-like shovels, with a clearance of 5 mm between theshovel and the wall surface, so that the packing fraction was 30 vol %.The main shaft was turned at 200 rpm, with the chopper remaining atrest. Ten seconds after the start of stirring, an aqueous solution ofacrylic acid/maleic acid copolymer sodium was added over 30 seconds, andgranulation and coating were carried out.

While the Loedige mixer was running, the lauric acid was added over 30seconds, and coating was carried out. Then the zeolite was added andstirring was continued for 30 seconds. Thus there were obtained coatedparticles.

The coated particles were classified by using a sieve with an opening of2000 μm. There were obtained particles 1 which had passed through thesieve. TABLE 6 Composition of particles 1 (wt % on net basis) Sodiumcarbonate[2] 85.5 Acrylic acid/maleic acid copolymer sodium 3.0 Lauricacid 2.0 Zeolite 4.0 Other minor components Balance Water content 5.0Total 100.0<Particles 2>

The components (except for zeolite for coating) shown in Table 7 weremixed together according to the prescribed ratio to-give a slurrycontaining 40% water at 70° C. Incidentally, the LAS—K was formed in theslurry by feeding LAS—H and KOH into the reaction system.

The slurry was transferred to the top of the drying tower (2 m indiameter and 5 m in effective length) by the plunger pump. Then theslurry was sprayed into the tower through a pressure nozzle (at apressure of 30 kg/cm²) for drying. During spray-drying, the drying towerwas kept at 260° C. (at the inlet of hot air) and 90-100° C. (at theoutlet of discharged air). The powder collected from the bottom of thetower was mixed with zeolite for coating. Thus there was obtained thespray-dried powder.

The spray-dried powder, nonionic surfactant, and water in a ratio of88.44:3.33:0.89 (by weight) were fed into the KRC kneader (Model S-4,from Kurimoto Tekkosho) to give a kneaded mixture at 60-70° C. Thethroughput was 180 kg/hr in terms of kneaded mixture. The kneadedmixture was fed into a pelleter having a die opening of 10 mmφ (ModelEXDFJS-60, from Fuji Paudal). There were obtained solid pellets, 10 mmφin diameter and 10-30 mm in average length.

The resulting solid detergent in pellet form and zeolite in a ratio of92.67:4.00 (by weight) were fed into the Fitz Mill together with coldair at 15° C. The flow rate was 6 Nm³/min. Crushing was carried out at athroughput of 188 kg/hr. Three sets of Fitz Mill arranged in series wereused. Fitz Mill is Model DKA-3 of Hosokawamicron. It has a fist-stagescreen with an opening of 12 mmφ, a second-stage screen with an openingof 6 mmφ, and a third-stage screen with an opening of 2.3 mmφ. It wasrun at a speed of 4700 rpm for all the stages.

The crushed particles were continuously fed, together with zeolite, intoa horizontal cylindrical rotary tumbling drum (with an Fr number of0.14, 0.70 m in diameter, 1.40 m long, inclined 3°, with 15 baffles,each measuring 1 mm thick, 50 mm high, and 350 mm long). The content inthe rotary drum was sprayed with a nonionic surfactant. Thus there wereobtained particles 2 as shown in Table 8. Incidentally, the ratio of thecrushed product, the zeolite, and the nonionic surfactant sprayed eachof which was fed into the rotary drum, was 96.67:3.00:0.33 (by weight).TABLE 7 Composition of spray-dried powder of particles 2 (wt % on netbasis) LAS-K 17.0 AOS-K 9.0 Soap 5.5 Zeolite (added to slurry) 21.0Zeolite (for coating) 2.0 Potassium carbonate 11.0 Sodium carbonate [2]24.0 Fluorescent agent 0.1 Water content 7.0 Other minor componentsBalance Total 100.0

TABLE 8 Composition of particles 2 (wt % on net basis) LAS-K 15.0 AOS-K8.0 Soap 4.9 Zeolite 25.9 Nonionic surfactant 3.3 Potassium carbonate9.7 Sodium carbonate [2] 21.2 Fluorescent agent 0.1 Water content 8.1Other minor components Balance Total 100.0<Particles 3>

The components (except for zeolite for coating) shown in Table 9 weremixed together according to the prescribed ratio to give a slurrycontaining 40% water at 70° C. Incidentally, the LAS—Na was formed inthe slurry by feeding LAS—H and NaOH into the reaction system.

This slurry was spray-dried in the drying tower under the same conditionas used for particles 2. The dried powder collected from the bottom ofthe tower was mixed with zeolite for coating. Thus there were obtainedparticles 3. TABLE 9 Composition of particles 3 (wt % on net basis)LAS-Na 17.9 AOS-Na 4.0 Sodium carbonate [2] 9.8 Calcium carbonate 5.0Sodium tripolyphosphate 14.9 Sodium silicate 11.9 Zeolite (for coating)3.5 Sodium sulfate 24.7 Water content 7.0 Other minor components BalanceTotal 100.0<Particles 4>

Of the components shown in Table 10 below, zeolite (main portion), whitecarbon, and sodium carbonate [1] were fed into a Loedige mixer (ModelM-20, from Matsubo) equipped with plough-like shovels, with a clearanceof 5 mm between the shovel and the wall surface, so that the packingfraction was 50 vol %. (Powder temperature: about 30° C.) For theirmixing, the main shaft and chopper were turned at 200 rpm and 6000 rpm,respectively, for 30 seconds.

With the main shaft and chopper running for about 60 seconds, the powdermixture was incorporated with a mixture of nonionic surfactant and12-hydroxystearic acid which had previously been prepared by melt-mixingat 85° C.

With the main shaft and chopper still running, the remaining portion ofzeolite was added and mixing was continued for 90 seconds. Then, zeolitefor coating was added and mixing was continued for 30 seconds. Theresulting mixture was discharged from the Loedige mixer.

The thus obtained particles were sifted through a sieve with an openingof 2000 μm to give particles 4 as desired. TABLE 10 Composition ofparticles 4 (wt % on net basis) Nonionic surfactant 23.012-hydroxystearic acid 4.0 Zeolite 33.0 (main/remaining/coating =24/5/4) White carbon 4.0 Sodium carbonate [1] 26.0 Water content 7.0Minor components Balance Total 100.0<Particles 5>

The components (except for zeolite for coating) shown in Table 11 weremixed together according to the prescribed ratio to give a slurrycontaining 50% water at 80° C. This slurry was spray-dried in the dryingtower under the same condition as used for particles 2. The dried powdercollected from the bottom of the tower was mixed with zeolite forcoating. Thus there were obtained particles 5. TABLE 11 Composition ofparticles 5 (wt % on net basis) Soap 30.0 Sodium carbonate [2] 40.0Potassium carbonate 5.0 Zeolite (for coating) 17.0 Water content 6.0Minor components Balance Total 100.0

TABLE 12 Example 32 33 34 35 36 37 Formulation Powder*¹⁰ 12.8 25.5 11.526.0 12.8 12.8 (%) Example 1 Example 1 Example 6 Example 1 Example 1Example 1 Particles 1 — — — — 10.0 20.0 Particles 2 86.3 73.6 — — 76.666.3 Particles 3 — — 87.6 73.1 — — Particles 4 — — — — — — Particles 5 —— — — — — Enzyme 0.7 0.7 0.7 0.8 0.3 0.7 Perfume 0.2 0.2 0.2 0.1 0.3 0.2Total 100.0 100.0 100.0 100.0 100.0 100.0 Properties Angle of ◯ ◯ ◯ ◯ ◯◯ repose Tendency to ◯ ◯ ◯ ◯ ◯ ◯ caking under pressure Odor ◯ ◯ ◯ ◯ ◯ ◯*¹⁰Powder containing α-sulfo fatty acid alkylester salt in highconcentrations (upper line: content in percent, lower line: Example inwhich the powder was produced)

TABLE 13 Example 38 39 40 41 42 43 Formulation Powder*¹⁰ 25.5 23.0 15.016.6 12.8 12.8 (%) Example 1 Example 6 Example 25 Example 30 Example 1Example 1 Particles 1 10.0 20.0 10.0 10.0 67.1 47.0 Particles 2 — — 74.8— — — Particles 3 64.2 56.8 — 73.2 — — Particles 4 — — — — 20.0 20.0Particles 5 — — — — — 20.0 Perfume 0.3 0.2 0.2 0.2 0.1 0.2 Total 100.0100.0 100.0 100.0 100.0 100.0 Properties Angle of ◯ ◯ ◯ ◯ ◯ ◯ reposeTendency to ◯ ◯ ◯ ◯ ◯ ◯ caking under pressure Odor ◯ ◯ ◯ ◯ ◯ ◯

TABLE 14 Example 44 45 46 47 48 Formulation Powder*¹⁰ 18.0 12.8 16.612.5 25.5 (%) Example 18 Example 25 Example 30 Example 1 Example 1Particles 1 41.6 37.0 43.1 20.0 20.0 Particles 2 — — — 27.3 24.3Particles 3 — — — — — Particles 4 20.0 20.0 20.0 20.0 20.0 Particles 520.0 30.0 20.0 20.0 10.0 Perfume 0.4 0.2 0.3 0.2 0.2 Total 100.0 100.0100.0 100.0 100.0 Properties Angle of ◯ ◯ ◯ ◯ ◯ repose Tendency to ◯ ◯ ◯◯ ◯ caking under pressure Odor ◯ ◯ ◯ ◯ ◯

Example 49

The powder containing α-sulfo fatty acid alkylester salt in highconcentrations and the components shown in Table 15 (except for nonionicsurfactant for spraying and zeolite for coating) were fed intoPlough-Shear Mixer (Model WB-75 from Pacific Machinery & Engineering),so that the Q-sulfo fatty acid alkylester sodium (obtained in Example 1)as the active ingredient in the mixture was 10%. Their formulation isshown in Table 15. Granulation was carried out for 5 minutes, with themain shaft rotating at 162 rpm and the chopper rotating at 6000 rpm.Zeolite for coating was added such that the ratio of the granules to beobtained to the zeolite was 93.64:5.25 (by weight). After mixing for 1minute, there were obtained granules. The granules were continuously fedinto a horizontal cylindrical rotary drum (with an Fr number of 0.14,0.70 m in diameter, 1.40 m long, inclined 3°, with 15 baffles, eachmeasuring 1 mm thick, 50 mm high, and 350 mm long). The content in therotary drum was sprayed with a nonionic surfactant for spraying. Thoseparticles remaining on the sieve having an opening of 2 mmφ wereremoved. Thus there was obtained the granular detergent as desired.Incidentally, the ratio of the granules (fed into the tumbling drum) tothe nonionic surfactant for spraying was 98.89:1.11 (by weight). Theproperties of the granular detergent are shown in Table 15.

Examples 50 to 52

The powder containing α-sulfo fatty acid alkylester salt and thecomponents shown in Table 15 (except for nonionic surfactant forspraying and zeolite for coating and as grind aid) were fed into KRCkneader (Model S-4, from Kurimoto), so that the α-sulfo fatty acidalkylester sodium (obtained in Example 1) as the active ingredient inthe mixture was as shown in Table 15. Their formulation is shown inTable 15. (The nonionic surfactant and soap were those which had theform shown in Table 15.) There was obtained a kneaded mixture at 60-70°C. The throughput was 150 kg/hr in terms of mixture. The kneaded mixturewas fed into a pelleter (Model EXDFJS-60, from Fuji Paudal) having a diediameter of 10 mmφ. Thus there were obtained solid pellets, 10 mmφ indiameter and 10-30 mm in average length.

The resulting solid pellets and zeolite (as a grinding aid) in a ratioof 91.76:5.25 (by weight) were fed into the Fitz Mill together with coldair at 15° C. The flow rate was 6 Nm³/min. Crushing was carried out at athroughput of 160 kg/hr. Three sets of Fitz Mill arranged in series wereused. Fitz Mill is Model DKA-3 of Hosokawamicron. It has a fist-stagescreen with an opening of 6 mmφ, a second-stage screen with an openingof 4 mmφ, and a third-stage screen with an opening of 2 mmφ, and afirst-stage blade rotating at 1880 rpm, a second-stage blade rotating at2350 rpm, and a third-stage blade rotating at 3760 rpm. Thus, there wereobtained crushed particles.

The crushed particles were continuously fed, together with zeolite forcoating, into a horizontal cylindrical rotary drum (with an Fr number of0.14, 0.70 m in diameter, 1.40 m long, inclined 3°, with 15 baffles,each measuring 1 mm thick, 50 mm high, and 350 mm long). The content inthe rotary drum was sprayed with a nonionic surfactant for spraying andperfume. Thus there was obtained the granular detergent as desired.Incidentally, the ratio of the crushed particles, the zeolite forcoating, and the nonionic surfactant for spraying each of which was fedinto the rotary drum, was 97.01:1.88:1.11 (by weight). The properties ofthe granular detergent are shown in Table 15. TABLE 15 Composition ofgranular detergent Example (wt % on net basis) 49 50 51 52 Method ofgranulation Mixing Kneading- Kneading- Kneading- Granulation crushingcrushing crushing Granulation Granulation Granulation α-sulfo fatty acid10.0 10.0 15.0 7.0 alkylester sodium Nonionic surfactant 4.0/1.0 4.0/1.03.0/1.0 8.0/1.0 (as major ingredient/ for spraying) Soap 8.0 8.0 8.0 8.0Form of soap and [1] [1] [2] [3] nonionic surfactant*¹¹ Zeolite26.6/0.0/4.2 24.8/4.2/1.5 27.8/4.2/1.5 27.8/4.2/1.5 (as major component/as grind aid/for coating) Sodium sulfite 1.5 1.0 1.0 1.0 Potassiumcarbonate 9.0 10.0 5.0 10.0 Sodium carbonate [1] 22.0 23.4 20.6 17.5Water 7.5 5.8 6.8 8.9 Perfume 0.4 0.3 0.3 0.3 Other minor componentsBalance Balance Balance Balance Total 100.0 100.0 100.0 100.0 PropertiesAngle of repose ◯ ◯ ◯ ◯ Tendency to ◯ ◯ ◯ ◯ caking under pressure Odor ◯◯ ◯ ◯*¹¹Form of soap and nonionic surfactant[1] Nonionic surfactant: Aqueous solution containing 90% activeingredient; Soap: Particles containing 93% active ingredient.[2] Nonionic surfactant/soap = concentrate of 3/8 mixture containing8.1% water.[3] Nonionic surfactant/soap = concentrate of 8/8 mixture containing18.8% water

Example 53

The raw materials were mixed according to the formulation shown in Table16 to give a slurry containing 40% water at 70° C. Incidentally, theLAS—K was formed in the slurry by feeding LAS—H and KOH into thereaction system. The α-sulfo fatty acid methylester sodium is the powderobtained in Example 1.

This slurry was spray-dried in the drying tower under the same conditionas used for particles 2. The dried powder collected from the bottom ofthe tower was mixed with zeolite for coating. Thus there were obtainedspray-dried particles. The properties of the spray-dried particles areshown in Table 16. TABLE 16 Composition and properties of spray-driedparticles (wt % on net basis) α-sulfo fatty acid alkylester sodium 11.8LAS-K 9.4 Soap 10.6 Maleic acid/acrylic acid copolymer sodium 1.2Zeolite 18.0 Zeolite (for coating) 2.1 Sodium sulfite 1.8 Potassiumcarbonate 10.6 Sodium carbonate [2] 26.1 Water content 4.5 Other minorcomponents Balance Total 100.0 Angle of repose ◯ Tendency to cakingunder pressure ◯ Odor ◯

Example 54

The spray-dried particles obtained in Example 53, nonionic surfactant,and water in a ratio of 85.09:3.89:3.09 (by weight) were fed into KRCkneader (Model S-4, from Kurimoto). There was obtained a kneaded mixtureat 60-70° C. The throughput was 180 kg/hr in terms of kneaded mixture.The kneaded mixture was fed into a pelleter (Model EXDFJS-60, from FujiPaudal) having a die diameter of 10 mmφ. Thus there were obtained solidpellets, 10 mmφ in diameter and 10-30 mm in average length.

The resulting solid pellets and zeolite in a ratio of 92.07:5.50 (byweight) were fed into the Fitz Mill together with cold air at 15° C. Theflow rate was 6 Nm³/min. Crushing was carried out at a throughput of 190kg/hr. Three sets of Fitz Mill arranged in series were used. Fitz Millis Model DKA-3 of Hosokawamicron. It has a fist-stage screen with anopening of 12 mmφ, a second-stage screen with an opening of 6 mmφ, and athird-stage screen with an opening of 2.5 mmφ, and all the stagesrunning at 4700 rpm. Thus, there were obtained crushed particles.

The crushed particles were continuously fed, together with zeolite, intoa horizontal cylindrical rotary drum (with an Fr number of 0.14, 0.70 min diameter, 1.40 m long, inclined 3°, with 15 baffles, each measuring 1mm thick, 50 mm high, and 350 mm long). The content in the rotary drumwas sprayed with a nonionic surfactant. Thus there was obtained thegranular detergent as desired. Incidentally, the ratio of the crushedparticles, the zeolite, and the nonionic surfactant sprayed each ofwhich was fed into the rotary drum, was 97.57:1.88:0.55 (by weight). Theproperties of the granular detergent are shown in Table 17. TABLE 17Composition and properties of granular detergent (wt % on net basis)α-sulfo fatty acid alkylester sodium 10.0 LAS-K 8.0 Nonionic surfactant4.0 Soap 9.0 Maleic acid/acrylic acid copolymer sodium 1.0 Zeolite 23.0Sodium sulfite 1.5 Potassium carbonate 9.0 Sodium carbonate [2] 22.2Water content 8.1 Other minor components Balance Total 100.0 Angle ofrepose ◯ Tendency to caking under pressure ◯ Odor ◯

Example 55

The spray-dried particles obtained in Example 53, nonionic surfactant,and water in a ratio of 88.66:3.89:1.39 (by weight) were fed intoPlough-Shear Mixer (Model WB-75 from Pacific Machinery & Engineering).Granulation was carried out for 5 minutes, with the main shaft rotatingat 162 rpm and the chopper rotating at 6000 rpm. Zeolite was added suchthat the ratio of the granules to the zeolite was 93.94:5.50 (byweight). After mixing for 1 minute, there were obtained granules. Thegranules were continuously fed into a horizontal cylindrical rotary drum(with an Fr number of 0.14, 0.70 m in diameter, 1.40 m long, inclined3°, with 15 baffles, each measuring 1 mm thick, 50 mm high, and 350 mmlong). The content in the tumbling drum was sprayed with a nonionicsurfactant. Those particles remaining on the sieve having an opening of2 mmφ were removed. Thus there was obtained the granular detergent asdesired. Incidentally, the ratio of the granules to the nonionicsurfactant sprayed each of which was fed into the rotary drum, was99.44:0.56 (by weight). The properties of the granular detergent areshown in Table 18. TABLE 18 Composition and properties of granulardetergent (wt % on net basis) α-sulfo fatty acid alkylester sodium 10.5LAS-K 8.3 Nonionic surfactant 4.0 Soap 9.4 Maleic acid/acrylic acidcopolymer sodium 1.1 Zeolite 22.2 Sodium sulfite 1.6 Potassium carbonate9.4 Sodium carbonate [2] 23.1 Water content 6.3 Other minor componentsBalance Total 100.0 Angle of repose ◯ Tendency to caking under pressure◯ Odor ◯

Examples 56 to 66

The raw materials and particles in a ratio shown in Tables 22 to 24 werefed into a horizontal cylindrical rotary drum (400 mm in diameter, 700mm long, with an Fr number of 0.3). Mixing was carried out for 2minutes, while spraying with perfume and water. The resulting mixturewas fed into KRC kneader (Model S-4, from Kurimoto), and mixed. Theresulting mixture was fed into a pelleter (Model EXDFJS-60, from FujiPaudal) having a die diameter of 100 mmφ. Thus there were obtained solidpellets. The solid pellets were mixed and formed into a solid detergentby using a vacuum two-stage prodder (from Nippon Kakoki). The eachresulting solid detergent was satisfactory in productivity and quality(detergency). Incidentally, the particles 6 to 17 were obtained by thefollowing process.

Composition and Preparation of Particles to be Mixed

<Particles 6 to 10>

The raw materials were mixed according to the formulation shown in Table19 to give a slurry containing 40% water at 70° C. Incidentally, theLAS—Na was formed in the slurry by feeding LAS—H and NaOH into thereaction system.

The resulting slurry was spray-dried under the same condition as usedfor particles 2. Dried particles were collected from the bottom of thetower. Thus there were obtained particles 6 to 10. TABLE 19 ParticlesParticles Particles Particles Particles Composition (%) 6 7 8 9 10LAS-Na 7.8 11.7 12.3 0.0 0.0 AOS-Na 4.5 4.3 4.9 6.0 0.0 Sodiumtripolyphosphate 11.2 10.6 9.9 12.0 11.0 Calcium carbonate 11.2 10.6 9.912.0 11.0 Sodium carbonate 19.0 16.0 18.5 20.0 20.0 Sodium sulfate 39.139.4 37.0 42.0 50.0 Fluorescent 0.01 0.01 0.01 0.02 0.02 whitening agentOther minor components Balance Balance Balance Balance Balance Watercontent 4.2 4.7 4.5 5.0 4.9 Total 100.0 100.0 100.0 100.0 100.0<Particles 11 to 14>

The raw materials (except for MES, LAS—H, and AOS—Na) according to theformulation shown in Table 20 were fed into a Loedige mixer (Model M-20,from Matsubo) equipped with plough-like shovels, with a clearance of 5mm between the shovel and the wall surface, so that the packing fractionwas 30 vol %. Mixing was carried out, with the main shaft and chopperrotating at 200 rpm and 3000 rpm, respectively. Thirty seconds after thestart of mixing, a solution of LAS—H was added for 2 minutes.

While mixing was continued, a solution of AOS—Na was added for 1 minuteand then MES (shown in Table 20) was added. Mixing was continued for 1minute. There were obtained particles.

The thus obtained particles were sifted through a sieve with an openingof 2000 μm to give particles 11 to 14. TABLE 20 (wt % on net basisexcept for MES) Particles Particles Particles Particles Composition (%)11 12 13 14 MES *¹² — — — 10.0 Example 1 LAS-Na 7.7 7.9 18.0 10.0 AOS-Na4.4 — 7.0 6.0 Sodium tripolyphosphate 11.0 11.3 10.0 10.0 Calciumcarbonate 11.0 11.3 10.0 10.0 Sodium carbonate 18.7 19.2 15.0 16.0Sodium sulfate 38.5 39.5 30.0 27.9 Fluorescent whitening 0.01 0.01 0.01— agent Other minor components Balance Balance Balance Balance Watercontent 6.1 8.0 7.3 7.6 Total 100.0 100.0 100.0 100.0*¹² The powder flakes, or pellets containing α-sulfo fatty acidalkylester salt in high concentrations, (upside: formulation, downside:Applicable example)<Particles 15 and 16>

The raw materials (except for MES, LAS—H, and AOS—Na) according to theformulation shown in Table 21 were fed into a Loedige mixer (Model M-20,from Matsubo) equipped with plough-like shovels, with a clearance of 5mm between the shovel and the wall surface, so that the packing fractionwas 30 vol %. Mixing was carried out, with the main shaft and chopperrotating at 200 rpm and 3000 rpm, respectively. Thirty seconds after thestart of mixing, a mixture of a solution of LAS—H and a solution ofAOS—Na was added for 3 minutes. Then MES shown in Table 21 was added.Mixing was continued for 1 minute. There were obtained particles.

The thus obtained particles were sifted through a sieve with an openingof 2000 μm to give particles 15 and 16.

<Particles 17>

The raw materials (except for MES, LAS—H, and AOS—Na) according to theformulation shown in Table 21 were fed into a Loedige mixer (Model M-20,from Matsubo) equipped with plough-like shovels, with a clearance of 5mm between the shovel and the wall surface, so that the packing fractionwas 30 vol %. Mixing was carried out for 30 seconds, with the main shaftand chopper rotating at 200 rpm and 3000 rpm, respectively. With mixingsuspended temporarily, a mixture of a solution of LAS—H and a solutionof AOS—Na was added for 15 seconds. Mixing was continued for 2 minutesunder the above-mentioned condition. Then MES shown in Table 21 wasadded. Mixing was continued for 1 minute. There were obtained particles.

The thus obtained particles were sifted through a sieve with an openingof 2000 μm to give particles 17. TABLE 21 (wt % on net basis except forMES) Particles Particles Particles Composition (%) 15 16 17 MES*¹² 10.0— 7.1 Example 6 Example 10 LAS-Na 10.6 10.0 8.2 AOS-Na — 6.0 4.1 Sodiumtripolyphosphate 12.0 — 11.2 Calcium carbonate 12.0 — 11.2 Sodiumcarbonate 18.0 25.0 16.3 Sodium sulfate 27.9 50.0 32.4 Fluorescentwhitening agent — 0.02 0.01 Other minor components Balance BalanceBalance Water content 7.6 6.2 7.0 Total 100.0 100.0 100.0*¹²Powder, flakes, or pellets containing α-sulfo fatty acid alkylestersalt in high concentrations (upper line: formulation, lower line:manufacturing method)

TABLE 22 Formulation Example Example Example Example (wt %) 56 57 58 59Particles 6 89.5 53.3 — — Particles 7 — — 94.0 — Particles 8 — — — 78.1MES*¹² 7.0 8.0 3.0 15.0 Example 1 Example 10 Example 1 Example 14 Sodium— 4.0 — — tripolyphosphate Calcium carbonate — 4.0 — — Sodium carbonate— 6.9 — — Sodium sulfate — 17.6 — — Perfume 0.3 0.3 0.2 0.3 Pigment 0.020.02 0.01 0.02 Other minor Balance Balance Balance Balance componentsWater content 2.9 4.5 2.7 3.8 (excluding water brought in by particles)Total 100.0 100.0 100.0 100.0

TABLE 23 Formulation Example Example Example Example (wt %) 60 61 62 63Particles 6 53.0 — — — Particles 9 — — — 28.0 Particles 10 — 38.9 29.3 —Particles 12 24.0 — — — Particles 13 — 55.5 — — Particles 14 — — 70.0 —Particles 15 — — — 70.0 MES*¹² 8.0 4.0 — — Example 1 Example 13 Sodiumsulfate 11.5 — — — Perfume 0.3 0.2 0.3 0.3 Pigment 0.02 0.01 0.02 0.02Other minor Balance Balance Balance Balance components Water content 2.71.2 0.3 1.4 (excluding water brought in by particles) Total 100.0 100.0100.0 100.0

TABLE 24 Formulation (wt %) Example 64 Example 65 Example 66 Particles11 90.9 — — Particles 16 — 65.0 — Particles 17 — — 98.0 MES*¹² 7.0 4.0 —Example 11 Example 1 Sodium — 13.0 — tripolyphosphate Calcium carbonate— 13.0 — Perfume 0.3 0.2 0.3 Pigment 0.02 0.02 0.02 Other minorcomponents Balance Balance Balance Water content 1.5 4.0 0.6 Total 100.0100.0 100.0

The raw materials used in Examples and Comparative Examples are shownbelow.

-   (1) Fatty Acid Methyl Ester

Fatty acid methyl ester as the raw material was prepared from esterifiedpalm oil (which is fatty acid methyl ester available under a trade nameof A, C: Edenor ME PA MY (from Cognis) and B: 2:8 (by weight) mixture ofPaster M-14 and Paster M-16 (from Lion Oleo chemical) by hydrogenationto reduce the iodine value for purification. Hydrogenation was carriedout in the usual way in the presence of a catalyst (“SO-850” from SakaiChemical Industry) (0.15% for the fatty acid methyl ester) at 170° C.for 8 hours. Table 25 shows the carbon distribution and properties ofthe fatty acid methyl ester-as the raw material. TABLE 25 B A Lion OleoC Cognis Chemical Cognis Long-chain C₁₀ 0-1 0-1 0-1 Distribution C₁₂ 0-10-1 0-1 (%) C₁₄ 1-2 18-22 1-2 C₁₆ 40-45 78-82 40-45 C₁₇ — 0-2 — C₁₈50-55 0-1 50-55 C₂₀ 0-1 — 0-1 Acid value Equal to or Equal to or Equalto or less than 1 less than 1 less than 1 Unsaponified Equal to or Equalto or Equal to or material less than 1 less than 1 less than 1 Watercontent Equal to or Equal to or Equal to or less than 0.5% less than0.5% less than 0.5% Iodine value 0.03 0.05 0.49 Average 285 264 285molecular weight

-   (2) Sulfonating gas: produced from SO₂ by catalytic oxidation with    dry air (with a dew point of −55° C.).-   (3) LAS—H: “Lipon LH-200” from Lion. Linear alkylbenzenesulfonic    acid having a C₁₀₋₁₄ alkyl group (96% active ingredient, with the    balance being unreacted alkylbenzene, sodium sulfate, water, etc.).    To be used as LAS—Na or LAS—K.-   (4) AOS—K: A 7:3 mixture of potassium a-olefin sulfonate and    potassium hydroxyalkylsulfonate (70% net, with the balance being    unreacted α-olefin, sodium sulfate, sultone, sodium hydroxide, and    water, etc). The olefin is a mixture composed of    C₁₄:C₁₆:C₁₈=15:50:35.-   (5) AOS—Na: “Liporan LB-440” from Lion.-   (6) Soap: Fatty acid sodium salt in which C₁₆:C₁₈:TMD (mixture of    C10-20 esters)=1:3:1 (67% active ingredient).-   (7) Nonionic surfactant: An alcohol ethoxylate which is adducted of    C₁₂₋₁₃ alcohol with 15 mol (on average) of ethylene oxide (90%    purity, with the balance being unreacted alcohol, PEG (polyethylene    glycol), water, etc.).-   (8) Methanol: Methanol (extra pure reagent) from Junsei Kagaku.-   (9) Sodium hydroxide: Flaky sodium hydroxide for food additive, from    Asahi Glass.-   (10) Potassium hydroxide: Flaky potassium hydroxide for food    additive, from Asahi Glass.-   (11) Hydrogen peroxide: 35% aqueous solution of hydrogen peroxide    (extra pure reagent), from Junsei Chemical.-   (12) Sodium carbonate [1]: Powder having an average particle    diameter of 10-60 μm, obtained by crushing from light soda ash    having a purity of 99% and a bulk density of 0.55 g/cm³, from Asahi    Glass.-   (13) Sodium carbonate [2]: Granular soda ash having a purity of 99%    and a bulk density of 1.07 g/cm³, from Asahi Glass.-   (14) Potassium carbonate: Food additive grade in crushed form having    a purity of 99% and a bulk density of 0.77 g/cm³, from Asahi Glass.-   (15) Sodium tripolyphosphate: Food additive grade, having a purity    of 85% and a bulk density of 0.97 g/cm³, from Taihei Chemical    Industry.-   (16) Zeolie: A type zeolite having a bulk density of 0.30 g/cm³,    “Silton B” from Mizusawa Chemical.-   (17) Sodium sulfate : Neutral anhydrous sodium sulfate in the form    of fine powder having an average particle diameter of 40-50 μm,    technical grade, from Shikoku Corp.-   (18) Potassium sulfate: In the form of fine powder having a particle    diameter of 20-30 μm, from Ueno Fine Chemical Industry.-   (19) Calcium carbonate: Guaranteed reagent, from Junsei Chemical.-   (20) Sodium sulfite: Anhydrous sodium sulfite from K. K.

Kamisu Kagaku Kogyo-sho.

-   (21) Maleic acid/acrylic acid copolymer sodium: “Aquaric TL-400” in    the form of 40% aqueous solution, from Nippon Shokubai.-   (22) Sodium polyacrylate: “Aquaric DL-100”, from Nippon Shokubai.-   (23) White carbon: “Tokuseal N” from Tokuyama.-   (24) Sodium citrate: Trisodium citrate dehydrate, extra pure, from    Junsei Chemical.-   (25) Calcium oxide: Calcium oxide powder, guaranteed reagent, from    Showa chemical Industry.-   (26) 12-hydroxystearic acid: 85% purity, from K F Trading.-   (27) Lauric acid: NAA-122 from NOF Corp.-   (28) Enzyme: Protease-lipase mixed enzyme, from Novonoldisc.-   (29) Perfume: Perfume composition A shown in Tables 11 to 18 in    Japanese Patent Laid-open No. 2002-146399.-   (30) Pigment: Ultramarine, from Dainichiseika Color & Chemicals Mfg.-   (31) Fluorescent whitening agent: AMS-GX from Ciba Specialty    Chemicals.

1. A process for producing powder, flakes, or pellets containing α-sulfofatty acid alkylester salt in high concentrations, said processcomprising: (1) a step of preparing a paste containing x-sulfo fattyacid alkylester salt by a series of reactions of sulfonating a fattyacid alkylester with a sulfonating gas by contact with each other,esterifying the sulfonated product with a lower alcohol, neutralizingthe esterified product, and bleaching the neutralized product, to give apaste containing x-sulfo fatty acid alkylester salt; (2) a step of agingthe thus obtained paste; (3) a step of making the aged paste into flakesor pellets containing equal to or less than 10 wt % of water, or a stepof making the aged paste into flakes or pellets containing equal to orless than 10 wt % of water and then crushing the resulting flakes orpellets into a powder having an average particle diameter of 100-1500μm; and (4) a step of aging the powder, flakes, or pellets.
 2. Theprocess as defined in claim 1, which further comprises a step of mixingthe powder, flakes, or pellets with an inorganic powder having anaverage particle diameter of 0.1-100 μm, in an amount of 1-40 wt % ofthe powder, flakes, or pellets.
 3. The process as defined in claim 1 or2 wherein the fatty acid alkylester has an iodine value equal to orlower than
 1. 4. Powder, flakes, or pellets containing o-sulfo fattyacid alkylester salt in high concentrations, which are obtained by theprocess defined in claim
 1. 5. The process for producing a granulardetergent which comprises mixing or granulating the powder, flakes, orpellets obtained by the process defined in claim 1 together with adetergent component by any method selected from powder mixing,kneading-crushing, and agitation granulation.
 6. The process forproducing a granular detergent which comprises mixing the powder,flakes, or pellets obtained by the process defined in claim 1 togetherwith a detergent component and water, to give a slurry containing 20-50wt % of water, and spray-drying the slurry.
 7. The process for producinga granular detergent which comprises mixing or granulating the granulardetergent obtained by the process defined in claim 5 or 6 further with adetergent component by any method selected from powder mixing,kneading-crushing, and agitation granulation.
 8. The granular detergentobtained by the process defined in claim 5 or
 6. 9. The process forproducing a solid detergent which comprises mixing and kneading thepowder, flakes, or pellets obtained by the process defined in claim 1together with a detergent component, to obtain solid detergent.